Part 10 out of 10
one chief cause of the intrusion of English plants in Australia, and not
vice versa, was the great importation of European seed to Australia and the
scanty return of Australian seed.)
I have now looked and found passage in F. Muller's (343/3. Ferdinand
Muller.) letter to me, in which he says: "In the WILDERNESSES of Australia
some European perennials are "advancing in sure progress," "not to be
arrested," etc. He gives as instances (so I suppose there are other cases)
eleven species, viz., 3. Rumex, Poterium sanguisorba, Potentilla anserina,
Medicago sativa, Taraxacum officinale, Marrubium vulgare, Plantago
lanceolata, P. major, Lolium perenne. All these are seeding freely. Now I
remember, years and years ago, your discussing with me how curiously easily
plants get naturalised on uninhabited islands, if ships even touch there.
I remember we discussed packages being opened with old hay or straw, etc.
Now think of hides and wool (and wool exported largely over Europe), and
plants introduced, and samples of corn; and I must think that if Australia
had been the old country, and Europe had been the Botany Bay, very few,
very much fewer, Australian plants would have run wild in Europe than have
now in Australia.
The case seems to me much stronger between La Plata and Spain.
Nevertheless, I will put in my one sentence on this head, illustrating the
greater migration during Glacial period from north to south than reversely,
very humbly and cautiously. (343/4. "Origin of Species," Edition I., page
379. Darwin refers to the facts given by Hooker and De Candolle showing a
stronger migratory flow from north to south than in the opposite direction.
Darwin accounts for this by the northern plants having been long subject to
severe competition in their northern homes, and having acquired a greater
"dominating power" than the southern forms. "Just in the same manner as we
see at the present day that very many European productions cover the ground
in La Plata, and in a lesser degree in Australia, and have to a certain
extent beaten the natives; whereas extremely few southern forms have become
naturalised in any part of Europe, though hides, wool, and other objects
likely to carry seeds have been largely imported during the last two or
three centuries from La Plata, and during the last thirty or forty years
I am very glad to hear you are making good progress with your Australian
Introduction. I am, thank God, more than half through my chapter on
geographical distribution, and have done the abstract of the Glacial
LETTER 344. TO J.D. HOOKER.
Down, March 30th, 1859.
Many thanks for your agreeable note. Please keep the geographical MS. till
you hear from me, for I may have to beg you to send it to Murray; as
through Lyell's intervention I hope he will publish, but he requires first
to see MS. (344/1. "The Origin of Species"; see a letter to Lyell in
"Life and Letters," II., page 151.)
I demur to what you say that we change climate of the world to account for
"migration of bugs, flies, etc." WE do nothing of the sort; for WE rest on
scored rocks, old moraines, arctic shells, and mammifers. I have no theory
whatever about cause of cold, no more than I have for cause of elevation
and subsidence; and I can see no reason why I should not use cold, or
elevation, or subsidence to explain any other phenomena, such as
distribution. I think if I had space and time I could make a pretty good
case against any great continental changes since the Glacial epoch, and
this has mainly led me to give up the Lyellian doctrine as insufficient to
explain all mutations of climate.
I was amused at the British Museum evidence. (344/2. This refers to the
letter to Murchison (Letter 65), published with the evidence of the 1858
enquiry by the Trustees of the British Museum.) I am made to give my
opinion so authoritatively on botanical matters!...
As for our belief in the origin of species making any difference in
descriptive work, I am sure it is incorrect, for I did all my barnacle work
under this point of view. Only I often groaned that I was not allowed
simply to decide whether a difference was sufficient to deserve a name.
I am glad to hear about Huxley--a wonderful man.
LETTER 345. TO J.D. HOOKER.
Wells Terrace, Ilkley, Otley, Yorkshire,
Thursday [before December 9th, 1859].
I have read your discussion (345/1. See "Introductory Essay," page c.
Darwin did not receive this work until December 23rd, so that the reference
is to proof-sheets.), as usual, with great interest. The points are
awfully intricate, almost at present beyond the confines of knowledge. The
view which I should have looked at as perhaps most probable (though it
hardly differs from yours) is that the whole world during the Secondary
ages was inhabited by marsupials, araucarias (Mem.--Fossil wood so common
of this nature in South America (345/2. See Letter 6, Note.)), Banksia,
etc.; and that these were supplanted and exterminated in the greater area
of the north, but were left alive in the south. Whence these very ancient
forms originally proceeded seems a hopeless enquiry.
Your remarks on the passage of the northern forms southward, and of the
southern forms of no kinds passing northward, seem to me grand. Admirable,
also, are your remarks on the struggle of vegetation: I find that I have
rather misunderstood you, for I feared I differed from you, which I see is
hardly the case at all. I cannot help suspecting that you put rather too
much weight to climate in the case of Australia. La Plata seems to present
such analogous facts, though I suppose the naturalisation of European
plants has there taken place on a still larger scale than in Australia...
You will get four copies of my book--one for self, and three for the
foreign botanists--in about ten days, or sooner; i.e., as soon as the
sheets can be bound in cloth. I hope this will not be too late for your
When you read my volume, use your pencil and score, so that some time I may
have a talk with you on any criticisms.
LETTER 346. TO HUGH FALCONER.
Down, December 17th, .
Whilst I think of it, let me tell you that years ago I remember seeing in
the Museum of the Geological Society a tooth of hippopotamus from
Madagascar: this, on geographical and all other grounds, ought to be
looked to. Pray make a note of this fact. (346/1. At a meeting of the
Geological Society, May 1st, 1833, a letter was read from Mr. Telfair to
Sir Alex. Johnstone, accompanying a specimen of recent conglomerate rock,
from the island of Madagascar, containing fragments of a tusk, and part of
a molar tooth of a hippopotamus ("Proc. Geol. Soc." 1833, page 479). There
is a reference to these remains of hippopotamus in a paper by Mr. R.B.
Newton in the "Geol. Mag." Volume X., 1893; and in Dr. Forsyth Major's
memoir on Megaladapis Madagascariensis ("Phil. Trans. R. Soc." Volume 185,
page 30, 1894).
Since this letter was written, several bones belonging to two or possibly
three species of hippopotamus have been found in Madagascar. See Forsyth
Major, "On the General Results of a Zoological Expedition to Madagascar in
1894-96" ("Proc. Zool. Soc." 1896, page 971.))
We have returned a week ago from Ilkley, and it has done me some decided
good. In London I saw Lyell (the poor man who has "rushed into the bosom
of two heresies"--by the way, I saw his celts, and how intensely
interesting), and he told me that you were very antagonistic to my views on
species. I well knew this would be the case. I must freely confess, the
difficulties and objections are terrific; but I cannot believe that a false
theory would explain, as it seems to me it does explain, so many classes of
facts. Do you ever see Wollaston? He and you would agree nicely about my
book (346/2. "Origin of Species," 1859.)--ill luck to both of you. If you
have anything at all pleasant for me to hear, do write; and if all that you
can say is very unpleasant, it will do you good to expectorate. And it is
well known that you are very fond of writing letters. Farewell, my good
old friend and enemy.
Do make a note about the hippopotamus. If you are such a gentleman as to
write, pray tell me how Torquay agrees with your health.
(PLATE: DR. ASA GRAY, 1867.)
LETTER 347. TO ASA GRAY.
Down, December 24th .
I have been for ten weeks at Water-cure, and on my return a fortnight ago
through London I found a copy of your Memoir, and heartily do I thank you
for it. (347/1. "Diagnostic Characters of New Species of Phaenogamous
Plants collected in Japan by Charles Wright...with Observations upon the
Relations of the Japanese Flora to that of North America and of other parts
of the Northern Temperate Zone" ("Mem. American Acad. Arts and Sci." Volume
VI., page 377, 1857).) I have not read it, and shall not be able very
soon, for I am much overworked, and my stomach has got nearly as bad as
With respect to the discussion on climate, I beg you to believe that I
never put myself for a moment in competition with Dana; but when one has
thought on a subject, one cannot avoid forming some opinion. What I wrote
to Hooker I forget, after reading only a few sheets of your Memoir, which I
saw would be full of interest to me. Hooker asked me to write to you, but,
as I told him, I would not presume to express an opinion to you without
careful deliberation. What he wrote I know not: I had previously several
years ago seen (by whom I forget) some speculation on warmer period in the
U. States subsequent to Glacial period; and I had consulted Lyell, who
seemed much to doubt, and Lyell's judgment is really admirably cautious.
The arguments advanced in your paper and in your letter seem to me hardly
sufficient; not that I should be at all sorry to admit this subsequent and
intercalated warmer period--the more changes the merrier, I think. On the
other hand, I do not believe that introduction of the Old World forms into
New World subsequent to the Glacial period will do for the modified or
representative forms in the two Worlds. There has been too much change in
comparison with the little change of isolated alpine forms; but you will
see this in my book. (347/2. "Origin of Species" (1859), Chapter XI.,
pages 365 et seq.) I may just make a few remarks why at first sight I do
not attach much weight to the argument in your letter about the warmer
climate. Firstly, about the level of the land having been lower
subsequently to Glacial period, as evidenced by the whole, etc., I doubt
whether meteorological knowledge is sufficient for this deduction: turning
to the S. hemisphere, it might be argued that a greater extent of water
made the temperature lower; and when much of the northern land was lower,
it would have been covered by the sea and intermigration between Old and
New Worlds would have been checked. Secondly, I doubt whether any
inference on nature of climate can be deduced from extinct species of
mammals. If the musk-ox and deer of great size of your Barren-Grounds had
been known only by fossil bones, who would have ventured to surmise the
excessively cold climate they lived under? With respect to food of large
animals, if you care about the subject will you turn to my discussion on
this subject partly in respect to the Elephas primigenius in my "Journal of
Researches" (Murray's Home and Colonial Library), Chapter V., page 85.
(347/3. "The firm conviction of the necessity of a vegetation possessing a
character of tropical luxuriance to support such large animals, and the
impossibility of reconciling this with the proximity of perpetual
congelation, was one chief cause of the several theories of sudden
revolutions of climate...I am far from supposing that the climate has not
changed since the period when these animals lived, which now lie buried in
the ice. At present I only wish to show that as far as quantity of food
alone is concerned, the ancient rhinoceroses might have roamed over the
steppes of Central Siberia even in their present condition, as well as the
living rhinoceroses and elephants over the karoos of Southern Africa"
("Journal of Researches," page 89, 1888).) In this country we infer from
remains of Elephas primigenius that the climate at the period of its
embedment was very severe, as seems countenanced by its woolly covering, by
the nature of the deposits with angular fragments, the nature of the co-
embedded shells, and co-existence of the musk-ox. I had formerly gathered
from Lyell that the relative position of the Megatherium and Mylodon with
respect to the Glacial deposits, had not been well made out; but perhaps it
has been so recently. Such are my reasons for not as yet admitting the
warmer period subsequent to Glacial epoch; but I daresay I may be quite
wrong, and shall not be at all sorry to be proved so.
I shall assuredly read your essay with care, for I have seen as yet only a
fragment, and very likely some parts, which I could not formerly clearly
understand, will be clear enough.
LETTER 348. TO J.D. HOOKER.
Down, [December] 26th, .
I have just read with intense interest as far as page xxvi (348/1. For
Darwin's impression of the "Introductory Essay to the Tasmanian Flora" as a
whole, see "Life and Letters," II., page 257.), i.e. to where you treat of
the Australian Flora itself; and the latter part I remember thinking most
of in the proof-sheets. Either you have altered a good deal, or I did not
see all or was purblind, for I have been much more interested with all the
first part than I was before,--not that I did not like it at first. All
seems to me very clearly written, and I have been baulked at only one
sentence. I think, on the whole, I like the geological, or rather
palaeontological, discussion best: it seems to me excellent, and admirably
cautious. I agree with all that you say as far as my want of special
knowledge allows me to judge.
I have no criticisms of any importance, but I should have liked more facts
in one or two places, which I shall not ask about. I rather demur to the
fairness of your comparison of rising and sinking areas (348/2. Hooker,
op. cit., page xv, paragraph 24. Hooker's view was that sinking islands
"contain comparatively fewer species and fewer peculiar generic types than
those which are rising." In Darwin's copy of the Essay is written on the
margin of page xvi: "I doubt whole case."), as in the Indian Ocean you
compare volcanic land with exclusively coral islands, and these latter are
very small in area and have very peculiar soil, and during their formation
are likely to have been utterly submerged, perhaps many times, and
restocked with existing plants. In the Pacific, ignorance of Marianne and
Caroline and other chief islands almost prevent comparison (348/3. Gambier
Island would be an interesting case. [Note in original.]); and is it right
to include American islands like Juan Fernandez and Galapagos? In such
lofty and probably ancient islands as Sandwich and Tahiti it cannot make
much difference in the flora whether they have sunk or risen a few thousand
feet of late ages.
I wish you could work in your notion of certain parts of the Tropics having
kept hot, whilst other parts were cooled; I tried this scheme in my mind,
and it seemed to fail. On the whole, I like very much all that I have read
of your Introduction, and I cannot doubt that it will have great weight in
converting other botanists from the doctrine of immutable creation. What a
lot of matter there is in one of your pages!
There are many points I wish much to discuss with you.
How I wish you could work out the Pacific floras: I remember ages ago
reading some of your MS. In Paris there must be, I should think, materials
from French voyages. But of all places in the world I should like to see a
good flora of the Sandwich Islands. (348/4. See Hillebrand, "Flora of the
Hawaiian Islands," 1888.) I would subscribe 50 pounds to any collector to
go there and work at the islands. Would it not pay for a collector to go
there, especially if aided by any subscription? It would be a fair
occasion to ask for aid from the Government grant of the Royal Society. I
think it is the most isolated group in the world, and the islands
themselves well isolated from each other.
LETTER 349. TO ASA GRAY.
Down, January 7th .
I have just finished your Japan memoir (349/1. "Diagnostic Characters of
New Species of Phaenogamous Plants collected in Japan by Charles Wright.
With observations upon the Relations of the Japanese Flora to that of North
America, etc.: 1857-59."--"Memoirs of Amer. Acad." VI.), and I must thank
you for the extreme interest with which I have read it. It seems to me a
most curious case of distribution; and how very well you argue, and put the
case from analogy on the high probability of single centres of creation.
That great man Agassiz, when he comes to reason, seems to me as great in
taking a wrong view as he is great in observing and classifying. One of
the points which has struck me as most remarkable and inexplicable in your
memoir is the number of monotypic (or nearly so) genera amongst the
representative forms of Japan and N. America. And how very singular the
preponderance of identical and representative species in Eastern, compared
with Western, America. I have no good map showing how wide the moderately
low country is on the west side of the Rocky Mountains; nor, of course, do
I know whether the whole of the low western territory has been botanised;
but it has occurred to me, looking at such maps as I have, that the eastern
area must be larger than the western, which would account to a certain
small extent for preponderance on eastern side of the representative
species. Is there any truth in this suspicion? Your memoir sets me
marvelling and reflecting. I confess I am not able quite to understand
your Geology at pages 447, 448; but you would probably not care to hear my
difficulties, and therefore I will not trouble you with them.
I was so grieved to get a letter from Dana at Florence, giving me a very
poor (though improved) account of his health.
LETTER 350. TO T.H. HUXLEY.
15, Marine Parade, Eastbourne, November 1st .
Your note has been wonderfully interesting. Your term, "pithecoid man," is
a whole paper and theory in itself. How I hope the skull of the new
Macrauchenia has come. It is grand. I return Hooker's letter, with very
many thanks. The glacial action on Lebanon is particularly interesting,
considering its position between Europe and Himalaya. I get more and more
convinced that my doctrine of mundane Glacial period is correct (350/1. In
the 1st edition of the "Origin," page 373, Darwin argues in favour of a
Glacial period practically simultaneous over the globe. In the 5th
edition, 1869, page 451, he adopted Mr. Croll's views on the alternation of
cold periods in the northern and southern hemispheres. An interesting
modification of the mundane Glacial period theory is given in Belt's "The
Naturalist in Nicaragua," 1874, page 265. Mr. Belt's views are discussed
in Wallace's "Geogr. Distribution," 1876, Volume I., page 151.), and that
it is the most important of all late phenomena with respect to distribution
of plants and animals. I hope your Review (350/2. The history of the
foundation of the "Natural History Review" is given in Huxley's "Life and
Letters," Volume I., page 209. See Letter 107.) progresses favourably. I
am exhausted and not well, so write briefly; for we have had nine days of
as much misery as man can endure. My poor daughter has suffered pitiably,
and night and day required three persons to support her. The crisis of
extreme danger is over, and she is rallying surprisingly, but the doctors
are yet doubtful of ultimate issue. But the suffering was so pitiable I
almost got to wish to see her die. She is easy now. When she will be fit
to travel home I know not. I most sincerely hope that Mrs. Huxley keeps up
pretty well. The work which most men have to do is a blessing to them in
such cases as yours. God bless you.
Sir H. Holland came here to see her, and was wonderfully kind.
LETTER 351. TO C. LYELL.
Down, November 20th .
I quite agree in admiration of Forbes' Essay (351/1. "Memoir of the
Geolog. Survey of the United Kingdom," Volume I., 1846.), yet, on my life,
I think it has done, in some respects, as much mischief as good. Those who
believe in vast continental extensions will never investigate means of
distribution. Good heavens, look at Heer's map of Atlantis! I thought his
division and lines of travel of the British plants very wild, and with
hardly any foundation. I quite agree with what you say of almost certainty
of Glacial epoch having destroyed the Spanish saxifrages, etc., in Ireland.
(351/2. See Letter 20.) I remember well discussing this with Hooker; and
I suggested that a slightly different or more equable and humid climate
might have allowed (with perhaps some extension of land) the plants in
question to have grown along the entire western shores between Spain and
Ireland, and that subsequently they became extinct, except at the present
points under an oceanic climate. The point of Devonshire now has a touch
of the same character.
I demur in this particular case to Forbes' transportal by ice. The subject
has rather gone out of my mind, and it is not worth looking to my MS.
discussion on migration during the Glacial period; but I remember that the
distribution of mammalia, and the very regular relation of the Alpine
plants to points due north (alluded to in "Origin"), seemed to indicate
continuous land at close of Glacial period.
LETTER 352. TO J.D. HOOKER.
Down, March 18th .
I have been recalling my thoughts on the question whether the Glacial
period affected the whole world contemporaneously, or only one longitudinal
belt after another. To my sorrow my old reasons for rejecting the latter
alternative seem to me sufficient, and I should very much like to know what
you think. Let us suppose that the cold affected the two Americas either
before or after the Old World. Let it advance first either from north or
south till the Tropics became slightly cooled, and a few temperate forms
reached the Silla of Caracas and the mountains of Brazil. You would say, I
suppose, that nearly all the tropical productions would be killed; and that
subsequently, after the cold had moderated, tropical plants immigrated from
the other non-chilled parts of the world. But this is impossible unless
you bridge over the tropical parts of the Atlantic--a doctrine which you
know I cannot admit, though in some respects wishing I could. Oswald Heer
would make nothing of such a bridge. When the Glacial period affected the
Old World, would it not be rather rash to suppose that the meridian of
India, the Malay Archipelago, and Australia were refrigerated, and Africa
not refrigerated? But let us grant that this was so; let us bridge over
the Red Sea (though rather opposed to the former almost certain
communication between the Red Sea and the Mediterranean); let us grant that
Arabia and Persia were damp and fit for the passage of tropical plants:
nevertheless, just look at the globe and fancy the cold slowly coming on,
and the plants under the tropics travelling towards the equator, and it
seems to me highly improbable that they could escape from India to the
still hot regions of Africa, for they would have to go westward with a
little northing round the northern shores of the Indian Ocean. So if
Africa were refrigerated first, there would be considerable difficulty in
the tropical productions of Africa escaping into the still hot regions of
India. Here again you would have to bridge over the Indian Ocean within so
very recent a period, and not in the line of the Laccadive Archipelago. If
you suppose the cold to travel from the southern pole northwards, it will
not help us, unless we suppose that the countries immediately north of the
northern tropic were at the same time warmer, so as to allow free passage
from India to Africa, which seems to me too complex and unsupported an
hypothesis to admit. Therefore I cannot see that the supposition of
different longitudinal belts of the world being cooled at different periods
helps us much. The supposition of the whole world being cooled
contemporaneously (but perhaps not quite equally, South America being less
cooled than the Old World) seems to me the simplest hypothesis, and does
not add to the great difficulty of all the tropical productions not having
been exterminated. I still think that a few species of each still existing
tropical genus must have survived in the hottest or most favourable spots,
either dry or damp. The tropical productions, though much distressed by
the fall of temperature, would still be under the same conditions of the
length of the day, etc., and would be still exposed to nearly the same
enemies, as insects and other animals; whereas the invading temperate
productions, though finding a favouring temperature, would have some of
their conditions of life new, and would be exposed to many new enemies.
But I fully admit the difficulty to be very great. I cannot see the full
force of your difficulty of no known cause of a mundane change of
temperature. We know no cause of continental elevations and depressions,
yet we admit them. Can you believe, looking to Europe alone, that the
intense cold, which must have prevailed when such gigantic glaciers
extended on the plains of N. Italy, was due merely to changed positions of
land within so recent a period? I cannot. It would be far too long a
story, but it could, I think, be clearly shown that all our continents
existed approximately in their present positions long before the Glacial
period; which seems opposed to such gigantic geographical changes necessary
to cause such a vast fall of temperature. The Glacial period endured in
Europe and North America whilst the level of the land oscillated in height
fully 3,000 feet, and this does not look as if changed level was the cause
of the Glacial period. But I have written an unreasonably long discussion.
Do not answer me at length, but send me a few words some time on the
I have had this copied, that it might not bore you too much to read it.
A few words more. When equatorial productions were dreadfully distressed
by fall of temperature, and probably by changed humidity, and changed
proportional numbers of other plants and enemies (though they might favour
some of the species), I must admit that they all would be exterminated if
productions exactly fitted, not only for the climate, but for all the
conditions of the equatorial regions during the Glacial period existed and
could everywhere have immigrated. But the productions of the temperate
regions would have probably found, under the equator, in their new homes
and soils, considerably different conditions of humidity and periodicity,
and they would have encountered a new set of enemies (a most important
consideration); for there seems good reason to believe that animals were
not able to migrate nearly to the extent to which plants did during the
Glacial period. Hence I can persuade myself that the temperate productions
would not entirely replace and exterminate the productions of the cooled
tropics, but would become partially mingled with them.
I am far from satisfied with what I have scribbled. I conclude that there
must have been a mundane Glacial period, and that the difficulties are much
the same whether we suppose it contemporaneous over the world, or that
longitudinal belts were affected one after the other. For Heaven's sake
LETTER 353. TO H.W. BATES.
March 26th .
I have been particularly struck by your remarks on the Glacial period.
(353/1. In his "Contributions to the Insect Fauna of the Amazon Valley,"
"Trans. Entom. Soc." Volume V., page 335 (read November 24th, 1860), Mr.
Bates discusses the migration of species from the equatorial regions after
the Glacial period. He arrives at a result which, he points out, "is
highly interesting as bearing upon the question of how far extinction is
likely to have occurred in equatorial regions during the time of the
Glacial epoch."..."The result is plain, that there has always (at least
throughout immense geological epochs) been an equatorial fauna rich in
endemic species, and that extinction cannot have prevailed to any extent
within a period of time so comparatively modern as the Glacial epoch in
geology." This conclusion does not support the view expressed in the
"Origin of Species" (Edition I., chapter XI., page 378) that the
refrigeration of the earth extended to the equatorial regions. (Bates,
loc. cit., pages 352, 353.)) You seem to me to have put the case with
admirable clearness and with crushing force. I am quite staggered with the
blow, and do not know what to think. Of late several facts have turned up
leading me to believe more firmly that the Glacial period did affect the
equatorial regions; but I can make no answer to your argument, and am
completely in a cleft stick. By an odd chance I have only a few days ago
been discussing this subject, in relation to plants, with Dr. Hooker, who
believes to a certain extent, but strongly urged the little apparent
extinction in the equatorial regions. I stated in a letter some days ago
to him that the tropics of S. America seem to have suffered less than the
Old World. There are many perplexing points; temperate plants seem to have
migrated far more than animals. Possibly species may have been formed more
rapidly within tropics than one would have expected. I freely confess that
you have confounded me; but I cannot yet give up my belief that the Glacial
period did to certain extent affect the tropics.
LETTER 354. TO J.D. HOOKER.
Down, February 25th .
I have almost finished your Arctic paper, and I must tell you how I admire
it. (354/1. "Outlines of the Distribution of Arctic Plants" [Read June
21st, 1860], "Linn. Soc. Trans." XXIII., 1862, page 251. The author's
remarks on Mr. Darwin's theories of Geographical Distribution are given at
page 255: they are written in a characteristically generous spirit.) The
subject, treated as you have treated it, is really magnificent. Good
Heaven, what labour it must have cost you! And what a grand prospect there
is for the future. I need not say how much pleased I am at your notice of
my work; for you know that I regard your opinion more than that of all
others. Such papers are the real engine to compel people to reflect on
modification of species; any one with an enquiring mind could hardly fail
to wish to consider the whole subject after reading your paper. By Jove!
you will be driven, nolens volens, to a cooled globe. Think of your own
case of Abyssinia and Fernando Po, and South Africa, and of your Lebanon
case (354/2. See "Origin," Edition VI., page 337.); grant that there are
highlands to favour migration, but surely the lowlands must have been
somewhat cooled. What a splendid new and original evidence and case is
that of Greenland: I cannot see how, even by granting bridges of
continuous land, one can understand the existing flora. I should think
from the state of Scotland and America, and from isothermals, that during
the coldest part of Glacial period, Greenland must have been quite
depopulated. Like a dog to his vomit, I cannot help going back and leaning
to accidental means of transport by ice and currents. How curious also is
the case of Iceland. What a splendid paper you have made of the subject.
When we meet I must ask you how much you attribute richness of flora of
Lapland to mere climate; it seems to me very marvellous that this point
should have been a sort of focus of radiation; if, however, it is
unnaturally rich, i.e. contains more species than it ought to do for its
latitude, in comparison with the other Arctic regions, would it not thus
falsely seem a focus of radiation? But I shall hereafter have to go over
and over again your paper; at present I am quite muddy on the subject. How
very odd, on any view, the relation of Greenland to the mountains of E. N.
America; this looks as if there had been wholesale extinction in E. N.
America. But I must not run on. By the way, I find Link in 1820
speculated on relation of Alpine and Arctic plants being due to former
colder climate, which he attributed to higher mountains cutting off the
warm southern winds.
LETTER 355. J.D. HOOKER TO CHARLES DARWIN.
Kew, November 2nd, 1862.
Did I tell you how deeply pleased I was with Gray's notice of my Arctic
essay? (355/1. "American Journal of Science and Arts," XXXIV., and in
Gray's "Scientific Papers," Volume I., page 122.) It was awfully good of
him, for I am sure he must have seen several blunders. He tells me that
Dr. Dawson (355/2. A letter (No. 144) by Sir J.D. Hooker, dated November
7th, 1862, on this subject occurs in the Evolutionary section.) is down on
me, and I have a very nice lecture on Arctic and Alpine plants from Dr. D.,
with a critique on the Arctic essay--which he did not see till afterwards.
He has found some mares' nests in my essay, and one very venial blunder in
the tables--he seems to HATE Darwinism--he accuses me of overlooking the
geological facts, and dwells much on my overlooking subsidence of temperate
America during Glacial period--and my asserting a subsidence of Arctic
America, which never entered into my head. I wish, however, if it would
not make your head ache too much, you would just look over my first three
pages, and tell me if I have outraged any geological fact or made any
oversights. I expounded the whole thing twice to Lyell before I printed
it, with map and tables, intending to get (and I thought I had) his
imprimatur for all I did and said; but when here three nights ago, I found
he was as ignorant of my having written an Arctic essay as could be! And
so I suppose he either did not take it in, or thought it of little
consequence. Hector approved of it in toto. I need hardly say that I set
out on biological grounds, and hold myself as independent of theories of
subsidence as you do of the opinions of physicists on heat of globe! I
have written a long [letter] to Dawson.
By the way, did you see the "Athenaeum" notice of L. Bonaparte's Basque and
Finnish language?--is it not possible that the Basques are Finns left
behind after the Glacial period, like the Arctic plants? I have often
thought this theory would explain the Mexican and Chinese national
affinities. I am plodding away at Welwitschia by night and Genera
Plantarum by day. We had a very jolly dinner at the Club on Thursday. We
are all well.
LETTER 356. TO J.D. HOOKER.
Down, November 4th .
I have read the pages (356/1. The paper on Arctic plants in Volume XXIII.
of the Linnean Society's "Transactions," 1860-62.) attentively (with even
very much more admiration than the first time) and cannot imagine what
makes Dr. D. accuse you of asserting a subsidence of Arctic America.
(356/2. The late Sir J.W. Dawson wrote a review (signed J.W.D) of Hooker's
Arctic paper which appeared in the "Canadian Naturalist," 1862, Volume
VII., page 334. The chief part of the article is made up of quotations
from Asa Gray's article referred to below. The remainder is a summary of
geological arguments against Hooker's views. We do not find the accusation
referred to above, which seems to have appeared in a lecture.) No doubt
there was a subsidence of N. America during the Glacial period, and over a
large part, but to maintain that the subsidence extended over nearly the
whole breadth of the continent, or lasted during the whole Glacial period,
I do not believe he can support. I suspect much of the evidence of
subsidence during the Glacial period there will prove false, as it largely
rests on ice-action, which is becoming, as you know, to be viewed as more
and more subaerial. If Dawson has published criticisms I should like to
see them. I have heard he is rabid against me, and no doubt partly in
consequence, against anything you write in my favour (and never was
anything published more favourable than the Arctic paper). Lyell had
difficulty in preventing Dawson reviewing the "Origin" (356/3. Dawson
reviewed the "Origin" in the "Canadian Naturalist," 1860.) on hearsay,
without having looked at it. No spirit of fairness can be expected from so
biassed a judge.
All I can say is that your few first pages have impressed me far more this
reading than the first time. Can the Scandinavian portion of the flora be
so potent (356/4. Dr. Hooker wrote: "Regarded as a whole the Arctic flora
is decidedly Scandinavian; for Arctic Scandinavia, or Lapland, though a
very small tract of land, contains by far the richest Arctic flora,
amounting to three-fourths of the whole"; he pointed out "that the
Scandinavian flora is present in every latitude of the globe, and is the
only one that is so" (quoted by Gray, loc. cit. infra).) from having been
preserved in that corner, warmed by the Gulf Stream, and from now alone
representing the entire circumpolar flora, during the warmer pre-Glacial
period? From the first I have not been able to resist the impression
(shared by Asa Gray, whose Review (356/5. Asa Gray's "Scientific Papers,"
Volume I., page 122.) on you pleased me much) that during the Glacial
period there must have been almost entire extinction in Greenland; for
depth of sea does not favour former southerly extension of land there.
(356/6. In the driving southward of the vegetation by the Glacial epoch
the Greenland flora would be "driven into the sea, that is, exterminated."
(Hooker quoted by Gray, loc. cit. page 124.) I must suspect that plants
have been largely introduced by sea currents, which bring so much wood from
N. Europe. But here we shall split as wide as the poles asunder. All the
world could not persuade me, if it tried, that yours is not a grand essay.
I do not quite understand whether it is this essay that Dawson has been
"down on." What a curious notion about Glacial climate, and Basques and
Finns! Are the Basques mountaineers--I hope so. I am sorry I have not
seen the "Athenaeum," but I now take in the "Parthenon." By the way, I
have just read with much interest Max Muller (356/7. Probably his
"Lectures on the Science of Language," 1861-64.); the last part, about
first origin of language, seems the least satisfactory part.
Pray thank Oliver heartily for his heap of references on poisons. (356/8.
Doubtless in connection with Darwin's work on Drosera: he was working at
this subject during his stay at Bournemouth in the autumn of 1862.) How
the devil does he find them out?
I must not indulge [myself] with Cypripedium. Asa Gray has made out pretty
clearly that, at least in some cases, the act of fertilisation is effected
by small insects being forced to crawl in and out of the flower in a
particular direction; and perhaps I am quite wrong that it is ever effected
by the proboscis.
I retract so far that if you have the rare C. hirsutissimum, I should very
much like to examine a cut single flower; for I saw one at a flower show,
and as far as I could see, it seemed widely different from other forms.
P.S.--Answer this, if by chance you can. I remember distinctly having read
in some book of travels, I am nearly sure in Australia, an account of the
natives, during famines, trying and cooking in all sorts of ways various
vegetable productions, and sometimes being injured by them. Can you
remember any such account? I want to find it. I thought it was in Sir G.
Grey, but it is not. Could it have been in Eyre's book?
LETTER 357. J.D. HOOKER TO CHARLES DARWIN.
...I have speculated on the probability of there having been a post-Glacial
Arctic-Norwego-Greenland in connection, which would account for the strong
fact, that temperate Greenland is as Arctic as Arctic Greenland is--a fact,
to me, of astounding force. I do confess, that a northern migration would
thus fill Greenland as it is filled, in so far as the whole flora
(temperate and Arctic) would be Arctic,--but then the same plants should
have gone to the other Polar islands, and above all, so many Scandinavian
Arctic plants should not be absent in Greenland, still less should whole
Natural Orders be absent, and above all the Arctic Leguminosae. It is
difficult (as I have told Dawson) to conceive of the force with which
arguments drawn from the absence of certain familiar ubiquitous plants
strike the botanists. I would not throw over altogether ice-transport and
water-transport, but I cannot realise their giving rise to such anomalies,
in the distribution, as Greenland presents. So, too, I have always felt
the force of your objection, that Greenland should have been depopulated in
the Glacial period, but then reflected that vegetation now ascends I forget
how high (about 1,000 feet) in Disco, in 70 deg, and that even in a Glacial
ocean there may always have been lurking-places for the few hundred plants
Greenland now possesses. Supposing Greenland were repeopled from
Scandinavia over ocean way, why should Carices be the chief things brought?
Why should there have been no Leguminosae brought, no plants but high
Arctic?--why no Caltha palustris, which gilds the marshes of Norway and
paints the housetops of Iceland? In short, to my eyes, the trans-oceanic
migration would no more make such an assemblage than special creations
would account for representative species--and no "ingenious wriggling" ever
satisfied me that it would. There, then!
I dined with Henry Christy last night, who was just returned from celt
hunting with Lartet, amongst the Basques,--they are Pyreneans. Lubbock was
there, and told me that my precious speculation was one of Von Baer's, and
that the Finns are supposed to have made the Kjokken moddings. I read Max
Muller a year ago--and quite agree, first part is excellent; last, on
origin of language, fatuous and feeble as a scientific argument.
LETTER 358. TO J.D. HOOKER.
Down, November 12th .
I return by this post Dawson's lecture, which seems to me interesting, but
with nothing new. I think he must be rather conceited, with his "If Dr.
Hooker had known this and that, he would have said so and so." It seems to
me absurd in Dawson assuming that North America was under sea during the
whole Glacial period. Certainly Greenland is a most curious and difficult
problem. But as for the Leguminosae, the case, my dear fellow, is as plain
as a pike-staff, as the seeds are so very quickly killed by the sea-water.
Seriously, it would be a curious experiment to try vitality in salt water
of the plants which ought to be in Greenland. I forget, however, that it
would be impossible, I suppose, to get hardly any except the Caltha, and if
ever I stumble on that plant in seed I will try it.
I wish to Heaven some one would examine the rocks near sea-level at the
south point of Greenland, and see if they are well scored; that would tell
something. But then subsidence might have brought down higher rocks to
present sea-level. I am much more willing to admit your Norwego-Greenland
connecting land than most other cases, from the nature of the rocks in
Spitzbergen and Bear Island. You have broached and thrown a lot of light
on a splendid problem, which some day will be solved. It rejoices me to
think that, when a boy, I was shown an erratic boulder in Shrewsbury, and
was told by a clever old gentleman that till the world's end no one would
ever guess how it came there.
It makes me laugh to think of Dr. Dawson's indignation at your sentence
about "obliquity of vision." (358/1. See Letter 144.) By Jove, he will
try and pitch into you some day. Good night for the present.
To return for a moment to the Glacial period. You might have asked Dawson
whether ibex, marmot, etc., etc., were carried from mountain to mountain in
Europe on floating ice; and whether musk ox got to England on icebergs?
Yet England has subsided, if we trust to the good evidence of shells alone,
more during Glacial period than America is known to have done.
For Heaven's sake instil a word of caution into Tyndall's ears. I saw an
extract that valleys of Switzerland were wholly due to glaciers. He cannot
have reflected on valleys in tropical countries. The grandest valleys I
ever saw were in Tahiti. Again, if I understand, he supposes that glaciers
wear down whole mountain ranges; thus lower their height, decrease the
temperature, and decrease the glaciers themselves. Does he suppose the
whole of Scotland thus worn down? Surely he must forget oscillation of
level would be more potent one way or another during such enormous lapses
of time. It would be hard to believe any mountain range has been so long
I suppose Lyell's book will soon be out. (358/2. "The Antiquity of Man,"
1863.) I was very glad to see in a newspaper that Murray sold 4,000. What
I am now working on cultivated plants, and rather like my work; but I am
horribly afraid I make the rashest remarks on value of differences. I
trust to a sort of instinct, and, God knows, can seldom give any reason for
my remarks. Lord, in what a medley the origin of cultivated plants is. I
have been reading on strawberries, and I can find hardly two botanists
agree what are the wild forms; but I pick out of horticultural books here
and there queer cases of variation, inheritance, etc., etc.
What a long letter I have scribbled; but you must forgive me, for it is a
great pleasure thus talking to you.
Did you ever hear of "Condy's Ozonised Water"? I have been trying it with,
I think, extraordinary advantage--to comfort, at least. A teaspoon, in
water, three or four times a day. If you meet any poor dyspeptic devil
like me, suggest it.
LETTER 359. TO J.D. HOOKER.
Down, 26th [March 1863].
I hope and think you are too severe on Lyell's early chapters. Though so
condensed, and not well arranged, they seemed to me to convey with uncommon
force the antiquity of man, and that was his object. (359/1. "The
Geological Evidences of the Antiquity of Man": London, 1863.) It did not
occur to me, but I fear there is some truth in your criticism, that nothing
is to be trusted until he [Lyell] had observed it.
I am glad to see you stirred up about tropical plants during Glacial
Remember that I have many times sworn to you that they coexisted; so, my
dear fellow, you must make them coexist. I do not think that greater
coolness in a disturbed condition of things would be required than the zone
of the Himalaya, in which you describe some tropical and temperate forms
commingling (359/2. "During this [the Glacial period], the coldest point,
the lowlands under the equator, must have been clothed with a mingled
tropical and temperate vegetation, like that described by Hooker as growing
luxuriantly at the height of from four to five thousand feet on the lower
slopes of the Himalaya, but with perhaps a still greater preponderance of
temperate forms" ("Origin of Species," Edition VI., page 338).); and as in
the lower part of the Cameroons, and as Seemann describes, in low mountains
of Panama. It is, as you say, absurd to suppose that such a genus as
Dipterocarpus (359/3. Dipterocarpus, a genus of the Dipterocarpaceae, a
family of dicotyledonous plants restricted to the tropics of the Old
World.) could have been developed since the Glacial era; but do you feel so
sure, as to oppose (359/4. The meaning seems to be: "Do you feel so sure
that you can bring in opposition a large body of considerations to show,
etc.") a large body of considerations on the other side, that this genus
could not have been slowly accustomed to a cooler climate? I see Lindley
says it has not been brought to England, and so could not have been tried
in the greenhouse. Have you materials to show to what little height it
ever ascends the mountains of Java or Sumatra? It makes a mighty
difference, the whole area being cooled; and the area perhaps not being in
all respects, such as dampness, etc., etc., fitted for such temperate
plants as could get in. But, anyhow, I am ready to swear again that
Dipterocarpus and any other genus you like to name did survive during a
About reversion you express just what I mean. I somehow blundered, and
mentally took literally that the child inherited from his grandfather.
This view of latency collates a lot of facts--secondary sexual characters
in each individual; tendency of latent character to appear temporarily in
youth; effect of crossing in educing talent, character, etc. When one
thinks of a latent character being handed down, hidden for a thousand or
ten thousand generations, and then suddenly appearing, one is quite
bewildered at the host of characters written in invisible ink on the germ.
I have no evidence of the reversion of all characters in a variety. I
quite agree to what you say about genius. I told Lyell that passage made
What a pity about Falconer! (359/5. This refers to Falconer's claim of
priority against Lyell. See "Life and Letters," III., page 14; also
Letters 166 and 168.) How singular and how lamentable!
Remember orchid pods. I have a passion to grow the seeds (and other
motives). I have not a fact to go on, but have a notion (no, I have a firm
conviction!) that they are parasitic in early youth on cryptogams! (359/6.
In an article on British Epiphytal Orchids ("Gard. Chron." 1884, page 144)
Malaxis paludosa is described by F.W. Burbidge as being a true epiphyte on
the stems of Sphagnum. Stahl states that the difficulty of cultivating
orchids largely depends on their dependence on a mycorhizal fungus,--though
he does not apply his view to germination. See Pringsheim's "Jahrbucher,"
XXXIV., page 581. We are indebted to Sir Joseph Hooker for the reference
to Burbidge's paper.) Here is a fool's notion. I have some planted on
Sphagnum. Do any tropical lichens or mosses, or European, withstand heat,
or grow on any trees in hothouse at Kew? If so, for love of Heaven, favour
my madness, and have some scraped off and sent me.
I am like a gambler, and love a wild experiment. It gives me great
pleasure to fancy that I see radicles of orchid seed penetrating the
Sphagnum. I know I shall not, and therefore shall not be disappointed.
LETTER 360. TO J.D. HOOKER.
Down [September 26th 1863].
...About New Zealand, at last I am coming round, and admit it must have
been connected with some terra firma, but I will die rather than admit
Australia. How I wish mountains of New Caledonia were well worked!...
LETTER 361. TO J.D. HOOKER.
(361/1. In the earlier part of this letter Mr. Darwin refers to a review
on Planchon in the "Nat. History Review," April 1865. There can be no
doubt, therefore, that "Thomson's article" must be the review of Jordan's
"Diagnoses d'especes nouvelles ou meconnues," etc., in the same number,
page 226. It deals with "lumpers" and "splitters," and a possible
April 17th .
I have been very much struck by Thomson's article; it seems to me quite
remarkable for its judgment, force, and clearness. It has interested me
greatly. I have sometimes loosely speculated on what nomenclature would
come to, and concluded that it would be trinomial. What a name a plant
will formally bear with the author's name after genus (as some recommend),
and after species and subspecies! It really seems one of the greatest
questions which can be discussed for systematic Natural History. How
impartially Thomson adjusts the claims of "hair-splitters" and "lumpers"!
I sincerely hope he will pretty often write reviews or essays. It is an
old subject of grief to me, formerly in Geology and of late in Zoology and
Botany, that the very best men (excepting those who have to write
principles and elements, etc.) read so little, and give up nearly their
whole time to original work. I have often thought that science would
progress more if there was more reading. How few read any long and
laborious papers! The only use of publishing such seems to be as a proof
that the author has given time and labour to his work.
LETTER 362. TO J.D. HOOKER.
Down, October 22nd and 28th, 1865.
As for the anthropologists being a bete noire to scientific men, I am not
surprised, for I have just skimmed through the last "Anthrop. Journal," and
it shows, especially the long attack on the British Association, a curious
spirit of insolence, conceit, dullness, and vulgarity. I have read with
uncommon interest Travers' short paper on the Chatham Islands. (362/1.
See Travers, H.H., "Notes on the Chatham Islands," "Linn. Soc. Journ." IX.,
October 1865. Mr. Travers says he picked up a seed of Edwardsia, evidently
washed ashore. The stranded logs indicated a current from New Zealand.) I
remember your pitching into me with terrible ferocity because I said I
thought the seed of Edwardsia might have been floated from Chili to New
Zealand: now what do you say, my young man, to the three young trees of
the same size on one spot alone of the island, and with the cast-up pod on
the shore? If it were not for those unlucky wingless birds I could believe
that the group had been colonised by accidental means; but, as it is, it
appears by far to me the best evidence of continental extension ever
observed. The distance, I see, is 360 miles. I wish I knew whether the
sea was deeper than between New Zealand and Australia. I fear you will not
admit such a small accident as the wingless birds having been transported
on icebergs. Do suggest, if you have a chance, to any one visiting the
Islands again, to look out for erratic boulders there. How curious his
statement is about the fruit-trees and bees! (362/2. "Since the
importation of bees, European fruit-trees and bushes have produced freely."
Travers, "Linn. Soc. Journal," IX., page 144.) I wish I knew whether the
clover had spread before the bees were introduced...
I saw in the "Gardeners' Chronicle" the sentence about the "Origin" dying
in Germany, but did not know it was by Seemann.
LETTER 363. TO C. LYELL.
Down, February 7th .
I am very much obliged for your note and the extract, which have interested
me extremely. I cannot disbelieve for a moment Agassiz on Glacial action
after all his experience, as you say, and after that capital book with
plates which he early published (363/1. "Etudes sur les Glaciers";
Neuchatel, 1840.); as for his inferences and reasoning on the valley of the
Amazon that is quite another question, nor can he have seen all the regions
to which Mrs. A. alludes. (363/2. A letter from Mrs. Agassiz to Lady
Lyell, which had been forwarded to Mr. Darwin. The same letter was sent
also to Sir Charles Bunbury, who, in writing to Lyell on February 3rd,
1866, criticises some of the statements. He speaks of Agassiz's
observations on glacial phenomena in Brazil as "very astonishing indeed; so
astonishing that I have very great difficulty in believing them. They
shake my faith in the glacial system altogether; or perhaps they ought
rather to shake the faith in Agassiz...If Brazil was ever covered with
glaciers, I can see no reason why the whole earth should not have been so.
Perhaps the whole terrestrial globe was once 'one entire and perfect
icicle.'" (From the privately printed "Life" of Sir Charles Bunbury,
edited by Lady Bunbury, Volume ii., page 334).) Her letter is not very
clear to me, and I do not understand what she means by "to a height of more
than three thousand feet." There are no erratic boulders (to which I
particularly attended ) in the low country round Rio. It is possible or
even probable that this area may have subsided, for I could detect no
evidence of elevation, or any Tertiary formations or volcanic action. The
Organ Mountains are from six to seven thousand feet in height; and I am
only a little surprised at their bearing the marks of glacial action. For
some temperate genera of plants, viz., Vaccinium, Andromeda, Gaultheria,
Hypericum, Drosera, Habenaria, inhabit these mountains, and I look at this
almost as good evidence of a cold period, as glacial action. That there
are not more temperate plants can be accounted for by the isolated position
of these mountains. There are no erratic boulders on the Pacific coast
north of Chiloe, and but few glaciers in the Cordillera, but it by no means
follows, I think, that there may not have been formerly gigantic glaciers
on the eastern and more humid side.
In the third edition of "Origin," page 403 (363/3. "Origin," Edition VI.,
page 335, 1882. "Mr. D. Forbes informs me that he found in various parts
of the Cordillera, from lat. 13 deg W. to 30 deg S., at about the height of
twelve thousand feet, deeply furrowed rocks...and likewise great masses of
detritus, including grooved pebbles. Along this whole space of the
Cordillera true glaciers do not now exist, even at much more considerable
height. "), you will find a brief allusion, on authority of Mr. D. Forbes,
on the former much lower extension of glaciers in the equatorial
Cordillera. Pray also look at page 407 at what I say on the nature of
tropical vegetation (which I could now much improve) during the Glacial
period. (363/4. "During this, the coldest period, the lowlands under the
Equator must have been clothed with a mingled tropical and temperate
vegetation..." ("Origin," Edition VI., 1882, page 338).)
I feel a strong conviction that soon every one will believe that the whole
world was cooler during the Glacial period. Remember Hooker's wonderful
case recently discovered of the identity of so many temperate plants on the
summit of Fernando Po, and on the mountains of Abyssinia. (363/5. "Dr.
Hooker has also lately shown that several of the plants living in the upper
parts of the lofty island of Fernando Po, and in the neighbouring Cameroon
Mountains, in the Gulf of Guinea, are closely related to those on the
mountains of Abyssinia, and likewise to those of temperate Europe" (loc.
cit., page 337).) I look at [it] as certain that these plants crossed the
whole of Africa from east to west during the same period. I wish I had
published a long chapter written in full, and almost ready for the press,
on this subject, which I wrote ten years ago. It was impossible in the
"Origin" to give a fair abstract.
My health is considerably improved, so that I am able to work nearly two
hours a day, and so make some little progress with my everlasting book on
domestic varieties. You will have heard of my sister Catherine's easy
death last Friday morning. (363/6. Catherine Darwin died in February
1866.) She suffered much, and we all look at her death as a blessing, for
there was much fear of prolonged and greater suffering. We are uneasy
about Susan, but she has hitherto borne it better than we could have hoped.
(363/7. Susan Darwin died in October 1866.)
Remember glacial action of Lebanon when you speak of no glacial action in
S. on Himalaya, and in S.E. Australia.
P.S.--I have been very glad to see Sir C. Bunbury's letter. (363/8. The
letter from Bunbury to Lyell, already quoted on this subject. Bunbury
writes: "There is nothing in the least NORTHERN, nothing that is not
characteristically Brazilian, in the flora of the Organ Mountains.") If
the genera which I name from Gardner (363/9. "Travels in the Interior of
Brazil," by G. Gardner: London, 1846.) are not considered by him as
usually temperate forms, I am, of course, silenced; but Hooker looked over
the MS. chapter some ten years ago and did not score out my remarks on
them, and he is generally ready enough to pitch into my ignorance and snub
me, as I often deserve. My wonder was how any, ever so few, temperate
forms reached the mountains of Brazil; and I supposed they travelled by the
rather high land and ranges (name forgotten) which stretch from the
Cordillera towards Brazil. Cordillera genera of plants have also, somehow,
reached the Silla of Caracas. When I think of the vegetation of New
Zealand and west coast of South America, where glaciers now descend to or
very near to the sea, I feel it rash to conclude that all tropical forms
would be destroyed by a considerably cooler period under the Equator.
LETTER 364. TO C. LYELL.
Down, Thursday, February 15th .
Many thanks for Hooker's letter; it is a real pleasure to me to read his
letters; they are always written with such spirit. I quite agree that
Agassiz could never mistake weathered blocks and glacial action; though the
mistake has, I know, been made in two or three quarters of the world. I
have often fought with Hooker about the physicists putting their veto on
the world having been cooler; it seems to me as irrational as if, when
geologists first brought forward some evidence of elevation and subsidence,
a former Hooker had declared that this could not possibly be admitted until
geologists could explain what made the earth rise and fall. It seems that
I erred greatly about some of the plants on the Organ Mountains. (364/1.
"On the Organ Mountains of Brazil some few temperate European, some
Antarctic, and some Andean genera were found by Gardner, which did not
exist in the low intervening hot countries" ("Origin," Edition VI., page
336).) But I am very glad to hear about Fuchsia, etc. I cannot make out
what Hooker does believe; he seems to admit the former cooler climate, and
almost in the same breath to spurn the idea. To retort Hooker's words, "it
is inexplicable to me" how he can compare the transport of seeds from the
Andes to the Organ Mountains with that from a continent to an island. Not
to mention the much greater distance, there are no currents of water from
one to the other; and what on earth should make a bird fly that distance
without resting many times? I do not at all suppose that nearly all
tropical forms were exterminated during the cool period; but in somewhat
depopulated areas, into which there could be no migration, probably many
closely allied species will have been formed since this period. Hooker's
paper in the "Natural History Review" (364/2. Possibly an unsigned
article, entitled "New Colonial Floras" (a review of Grisebach's "Flora of
the British West Indian Islands" and Thwaites' "Enumeratio Plantarum
Zeylaniae").--"Nat. Hist. Review," January 1865, page 46. See Letter 184.)
is well worth studying; but I cannot remember that he gives good grounds
for his conviction that certain orders of plants could not withstand a
rather cooler climate, even if it came on most gradually. We have only
just learnt under how cool a temperature several tropical orchids can
flourish. I clearly saw Hooker's difficulty about the preservation of
tropical forms during the cool period, and tried my best to retain one spot
after another as a hothouse for their preservation; but it would not hold
good, and it was a mere piece of truckling on my part when I suggested that
longitudinal belts of the world were cooled one after the other. I shall
very much like to see Agassiz's letter, whenever you receive one. I have
written a long letter; but a squabble with or about Hooker always does me a
world of good, and we have been at it many a long year. I cannot
understand whether he attacks me as a wriggler or a hammerer, but I am very
sure that a deal of wriggling has to be done.
LETTER 365. TO J.D. HOOKER.
Down, July 30th .
Many thanks about the lupin. Your letter has interested me extremely, and
reminds me of old times. I suppose, by your writing, you would like to
hear my notions. I cannot admit the Atlantis connecting Madeira and Canary
Islands without the strongest evidence, and all on that side (365/1. Sir
J.D. Hooker lectured on "Insular Floras" at the Nottingham meeting of the
British Association on August 27th, 1866. His lecture is given in the
"Gardeners' Chronicle," 1867, page 6. No doubt he was at this time
preparing his remarks on continental extension, which take the form of a
judicial statement, giving the arguments and difficulties on both sides.
He sums up against continental extension, which, he says, accounts for
everything and explains nothing; "whilst the hypothesis of trans-oceanic
migration, though it leaves a multitude of facts unexplained, offers a
rational solution of many of the most puzzling phenomena." In his lecture,
Sir Joseph wrote that in ascending the mountains in Madeira there is but
little replacement of lowland species by those of a higher northern
latitude. "Plants become fewer and fewer as we ascend, and their places
are not taken by boreal ones, or by but very few."): the depth is so
great; there is nothing geologically in the islands favouring the belief;
there are no endemic mammals or batrachians. Did not Bunbury show that
some Orders of plants were singularly deficient? But I rely chiefly on the
large amount of specific distinction in the insects and land-shells of P.
Santo and Madeira: surely Canary and Madeira could not have been
connected, if Madeira and P. Santo had long been distinct. If you admit
Atlantis, I think you are bound to admit or explain the difficulties.
With respect to cold temperate plants in Madeira, I, of course, know not
enough to form an opinion; but, admitting Atlantis, I can see their rarity
is a great difficulty; otherwise, seeing that the latitude is only a little
north of the Persian Gulf, and seeing the long sea-transport for seeds, the
rarity of northern plants does not seem to me difficult. The immigration
may have been from a southerly direction, and it seems that some few
African as well as coldish plants are common to the mountains to the south.
Believing in occasional transport, I cannot feel so much surprise at there
being a good deal in common to Madeira and Canary, these being the nearest
points of land to each other. It is quite new and very interesting to me
what you say about the endemic plants being in so large a proportion rare
species. From the greater size of the workshop (i.e., greater competition
and greater number of individuals, etc.) I should expect that continental
forms, as they are occasionally introduced, would always tend to beat the
insular forms; and, as in every area, there will always be many forms more
or less rare tending towards extinction, I should certainly have expected
that in islands a large proportion of the rarer forms would have been
insular in their origin. The longer the time any form has existed in an
island into which continental forms are occasionally introduced, by so much
the chances will be in favour of its being peculiar or abnormal in nature,
and at the same time scanty in numbers. The duration of its existence will
also have formerly given it the best chance, when it was not so rare, of
being widely distributed to adjoining archipelagoes. Here is a wriggle:
the older a form is, the better the chance will be of its having become
developed into a tree! An island from being surrounded by the sea will
prevent free immigration and competition, hence a greater number of ancient
forms will survive on an island than on the nearest continent whence the
island was stocked; and I have always looked at Clethra (365/2. Clethra is
an American shrubby genus of Ericaceae, found nowhere nearer to Madeira
than North America. Of this plant and of Persea, Sir Charles Lyell
("Principles," 1872, Volume II., page 422) says: "Regarded as relics of a
Miocene flora, they are just such forms as we should naturally expect to
have come from the adjoining Miocene continent." See also "Origin of
Species," Edition VI., page 83, where a similar view is quoted from Heer.)
and the other extra-European forms as remnants of the Tertiary flora which
formerly inhabited Europe. This preservation of ancient forms in islands
appears to me like the preservation of ganoid fishes in our present
freshwaters. You speak of no northern plants on mountains south of the
Pyrenees: does my memory quite deceive me that Boissier published a long
list from the mountains in Southern Spain? I have not seen Wollaston's,
"Catalogue," (365/4. Probably the "Catalogue of the Coleopterous Insects
of the Canaries in the British Museum," 1864.) but must buy it, if it gives
the facts about rare plants which you mention.
And now I have given more than enough of my notions, which I well know will
be in flat contradiction with all yours.
Wollaston, in his "Insecta Maderensia" (365/5. "Insecta Maderensia,"
London, 1854.), 4to, page 12, and in his "Variation of Species," pages 82-
7, gives the case of apterous insects, but I remember I worked out some
I think he gives in these same works the proportion of European insects.
LETTER 366. TO J.D. HOOKER.
(366/1. Sir Joseph had asked (July 31st, 1866): "Is there an evidence
that the south of England and of Ireland were not submerged during the
Glacial epoch, when the W. and N. of England were islands in a glacial sea?
And supposing they were above water, could the present Atlantic and N.W. of
France floras we now find there have been there during the Glacial epoch?--
Yet this is what Forbes demands, page 346. At page 347 he sees this
objection, and wriggles out of his difficulty by putting the date of the
Channel 'towards the close of the Glacial epoch.' What does Austen make
the date of the Channel?--ante or post Glacial?" The changes in level and
other questions are dealt with in a paper by R.A.C. Austen (afterwards
Godwin-Austen), "On the Superficial Accumulations of the Coasts of the
English Channel and the Changes they indicate." "Quart. Journ. Geol. Soc."
VII., 1851, page 118. Obit. notice by Prof. Bonney in the "Proc. Geol.
Soc." XLI., page 37, 1885.)
Down, August 3rd .
I will take your letter seriatim. There is good evidence that S.E. England
was dry land during the Glacial period. I forget what Austen says, but
Mammals prove, I think, that England has been united to the Continent since
the Glacial period. I don't see your difficulty about what I say on the
breaking of an isthmus: if Panama was broken through would not the fauna
of the Pacific flow into the W. Indies, or vice versa, and destroy a
multitude of creatures? Of course I'm no judge, but I thought De Candolle
had made out his case about small areas of trees. You will find at page
112, 3rd edition "Origin," a too concise allusion to the Madeira flora
being a remnant of the Tertiary European flora. I shall feel deeply
interested by reading your botanical difficulties against occasional
immigration. The facts you give about certain plants, such as the heaths,
are certainly very curious. (366/2. In Hooker's lecture he gives St.
Dabeoc's Heath and Calluna vulgaris as the most striking of the few boreal
plants in the Azores. Darwin seems to have been impressed by the boreal
character of the Azores, thus taking the opposite view to that of Sir
Joseph. See Letter 370, note.) I thought the Azores flora was more
boreal, but what can you mean by saying that the Azores are nearer to
Britain and Newfoundland than to Madeira?--on the globe they are nearly
twice as far off. (366/3. See Letter 368.) With respect to sea currents,
I formerly made enquiries at Madeira, but cannot now give you the results;
but I remember that the facts were different from what is generally stated:
I think that a ship wrecked on the Canary Islands was thrown up on the
coast of Madeira.
You speak as if only land-shells differed in Madeira and Porto Santo: does
my memory deceive me that there is a host of representative insects?
When you exorcise at Nottingham occasional means of transport, be honest,
and admit how little is known on the subject. Remember how recently you
and others thought that salt water would soon kill seeds. Reflect that
there is not a coral islet in the ocean which is not pretty well clothed
with plants, and the fewness of the species can hardly with justice be
attributed to the arrival of few seeds, for coral islets close to other
land support only the same limited vegetation. Remember that no one knew
that seeds would remain for many hours in the crops of birds and retain
their vitality; that fish eat seeds, and that when the fish are devoured by
birds the seeds can germinate, etc. Remember that every year many birds
are blown to Madeira and to the Bermudas. Remember that dust is blown
1,000 miles over the Atlantic. Now, bearing all this in mind, would it not
be a prodigy if an unstocked island did not in the course of ages receive
colonists from coasts whence the currents flow, trees are drifted and birds
are driven by gales. The objections to islands being thus stocked are, as
far as I understand, that certain species and genera have been more freely
introduced, and others less freely than might have been expected. But then
the sea kills some sorts of seeds, others are killed by the digestion of
birds, and some would be more liable than others to adhere to birds' feet.
But we know so very little on these points that it seems to me that we
cannot at all tell what forms would probably be introduced and what would
not. I do not for a moment pretend that these means of introduction can be
proved to have acted; but they seem to me sufficient, with no valid or
heavy objections, whilst there are, as it seems to me, the heaviest
objections on geological and on geographical distribution grounds (pages
387, 388, "Origin" (366/4. Edition III., or Edition VI., page 323.) to
Forbes' enormous continental extensions. But I fear that I shall and have
LETTER 367. J.D. HOOKER TO CHARLES DARWIN.
(367/1. In a letter of July 31st, Sir J.D. Hooker wrote, "You must not
suppose me to be a champion of continental connection, because I am not
agreeable to trans-oceanic migration...either hypothesis appears to me well
to cover the facts of oceanic floras, but there are grave objections to
both, botanical to yours, geological to Forbes'.")
The following interesting letters give some of Sir Joseph's difficulties.)
Kew, August 4th, 1866.
You mention ("Journal") no land-birds, except introduced, upon St. Helena.
Beatson (Introduction xvii) mentions one (367/2. Aegialitis sanctae-
helenae, a small plover "very closely allied to a species found in South
Africa, but presenting certain differences which entitle it to the rank of
a peculiar species" (Wallace, "Island Life," page 294). In the earlier
editions of the "Origin" (e.g. Edition III., page 422) Darwin wrote that
"Madeira does not possess one peculiar bird." In Edition IV., 1866, page
465, the mistake was put right.) "in considerable numbers," resembles sand-
lark--is called "wire bird," has long greenish legs like wires, runs fast,
eyes large, bill moderately long, is rather shy, does not possess much
powers of flight. What was it? I have written to ask Sclater, also about
birds of Madeira and Azores. It is a very curious thing that the Azores do
not contain the (non-European) American genus Clethra, that is found in
Madeira and Canaries, and that the Azores contain no trace of American
element (beyond what is common to Madeira), except a species of Sanicula, a
genus with hooked bristles to the small seed-vessels. The European
Sanicula roams from Norway to Madeira, Canaries, Cape Verde, Cameroons,
Cape of Good Hope, and from Britain to Japan, and also is, I think, in N.
America; but does not occur in the Azores, where it is replaced by one that
is of a decidedly American type.
This tells heavily against the doctrine that joins Atlantis to America, and
is much against your trans-oceanic migration--for considering how near the
Azores are to America, and in the influence of the Gulf-stream and
prevalent winds, it certainly appears marvellous. Not only are the Azores
in a current that sweeps the coast of U. States, but they are in the S.W.
winds, and in the eye of the S.W. hurricanes!
I suppose you will answer that the European forms are prepotent, but this
is riding prepotency to death.
R.T. Lowe has written me a capital letter on the Madeiran, Canarian, and
Cape Verde floras.
I misled you if I gave you to understand that Wollaston's Catalogue said
anything about rare plants. I am worked and worried to death with this
lecture: and curse myself as a soft headed and hearted imbecile to have
LETTER 368. J.D. HOOKER TO CHARLES DARWIN.
Kew, Monday [August 6th, 1866].
Again thanks for your letter. You need not fear my not doing justice to
your objections to the continental hypothesis!
Referring to page 344 again (368/1. "Origin of Species," Edition III.,
pages 343-4: "In some cases, however, as by the breaking of an isthmus and
the consequent irruption of a multitude of new inhabitants, or by the final
subsidence of an island, the extinction may have been comparatively
rapid."), it never occurred to me that you alluded to extinction of marine
life: an isthmus is a piece of land, and you go on in the same sentence
about "an island," which quite threw me out, for the destruction of an
isthmus makes an island!
I surely did not say Azores nearer to Britain and Newfoundland "than to
Madeira," but "than Madeira is to said places."
With regard to the Madeiran coleoptera I rely very little on local
distribution of insects--they are so local themselves. A butterfly is a
great rarity in Kew, even a white, though we are surrounded by market
gardens. All insects are most rare with us, even the kinds that abound on
the opposite side of Thames.
So with shells, we have literally none--not a Helix even, though they
abound in the lanes 200 yards off the Gardens. Of the 89 Dezertas insects
[only?] 11 are peculiar. Of the 162 Porto Santan 113 are Madeiran and 51
Never mind bothering Murray about the new edition of the "Origin" for me.
You will tell me anything bearing on my subject.
LETTER 369. J.D. HOOKER TO CHARLES DARWIN.
Kew, August 7th, 1866.
Dear old Darwin,
You must not let me worry you. I am an obstinate pig, but you must not be
miserable at my looking at the same thing in a different light from you. I
must get to the bottom of this question, and that is all I can do. Some
cleverer fellow one day will knock the bottom out of it, and see his way to
explain what to a botanist without a theory to support must be very great
difficulties. True enough, all may be explained, as you reason it will
be--I quite grant this; but meanwhile all is not so explained, and I cannot
accept a hypothesis that leaves so many facts unaccounted for. You say the
temperate parts of N. America [are] nearly two and a half times as distant
from the Azores as Europe is. According to a rough calculation on Col.
James' chart I make E. Azores to Portugal 850, West do. to Newfoundland
1500, but I am writing to a friend at Admiralty to have the distance
calculated (which looks like cracking nuts with Nasmyth's hammer!)
Are European birds blown to America? Are the Azorean erratics an
established fact? I want them very badly, though they are not of much
consequence, as a slight sinking would hide all evidence of that sort.
I do want to sum up impartially, leaving the verdict to jury. I cannot do
this without putting all difficulties most clearly. How do you know how
you would fare with me if you were a continentalist! Then too we must
recollect that I have to meet a host who are all on the continental side--
in fact, pretty nearly all the thinkers, Forbes, Hartung, Heer, Unger,
Wollaston, Lowe (Wallace, I suppose), and now Andrew Murray. I do not
regard all these, and snap my fingers at all but you; in my inmost soul I
conscientiously say I incline to your theory, but I cannot accept it as an
established truth or unexceptionable hypothesis.
The "Wire bird" being a Grallator is a curious fact favourable to you...How
I do yearn to go out again to St. Helena.
Of course I accept the ornithological evidence as tremendously strong,
though why they should get blown westerly, and not change specifically, as
insects, shells, and plants have done, is a mystery.
LETTER 370. TO J.D. HOOKER.
Down, August 8th .
It would be a very great pleasure to me if I could think that my letters
were of the least use to you. I must have expressed myself badly for you
to suppose that I look at islands being stocked by occasional transport as
a well-established hypothesis. We both give up creation, and therefore
have to account for the inhabitants of islands either by continental
extensions or by occasional transport. Now, all that I maintain is that of
these two alternatives, one of which must be admitted, notwithstanding very
many difficulties, occasional transport is by far the most probable. I go
thus far further--that I maintain, knowing what we do, that it would be
inexplicable if unstocked islands were not stocked to a certain extent at
least by these occasional means. European birds are occasionally driven to
America, but far more rarely than in the reverse direction: they arrive
via Greenland (Baird); yet a European lark has been caught in Bermuda.
By the way, you might like to hear that European birds regularly migrate
via the northern islands to Greenland.
About the erratics in the Azores see "Origin," page 393. (370/1.
"Origin," Edition VI., page 328. The importance of erratic blocks on the
Azores is in showing the probability of ice-borne seeds having stocked the
islands, and thus accounting for the number of European species and their
unexpectedly northern character. Darwin's delight in the verification of
his theory is described in a letter to Sir Joseph of April 26th, 1858, in
the "Life and Letters," II., page 112.) Hartung could hardly be mistaken
about granite blocks on a volcanic island.
I do not think it a mystery that birds have not been modified in Madeira.
(370/2. "Origin," Edition VI., page 328. Madeira has only one endemic
bird. Darwin accounts for the fact from the island having been stocked
with birds which had struggled together and become mutually co-adapted on
the neighbouring continents. "Hence, when settled in their new homes, each
kind will have been kept by the others in its proper place and habits, and
will consequently have been but little liable to modification." Crossing
with frequently arriving immigrants will also tend to keep down
modification.) Pray look at page 422 of "Origin" [Edition III.]. You
would not think it a mystery if you had seen the long lists which I have
(somewhere) of the birds annually blown, even in flocks, to Madeira. The
crossed stock would be the more vigorous.
Remember if you do not come here before Nottingham, if you do not come
afterwards I shall think myself diabolically ill-used.
LETTER 371. J.D. HOOKER TO CHARLES DARWIN.
Kew, August 9th, 1866.
If my letters did not gene you it is impossible that you should suppose
that yours were of no use to me! I would throw up the whole thing were it
not for correspondence with you, which is the only bit of silver in the
affair. I do feel it disgusting to have to make a point of a speciality in
which I cannot see my way a bit further than I could before I began. To be
sure, I have a very much clearer notion of the pros and cons on both sides
(though these were rather forgotten facts than rediscoveries). I see the
sides of the well further down more distinctly, but the bottom is as
obscure as ever.
I think I know the "Origin" by heart in relation to the subject, and it was
reading it that suggested the queries about Azores boulders and Madeira
birds. The former you and I have talked over, and I thought I remembered
that you wanted it confirmed. The latter strikes me thus: why should
plants and insects have been so extensively changed and birds not at all?
I perfectly understand and feel the force of your argument in reference to
birds per se, but why do these not apply to insects and plants? Can you
not see that this suggests the conclusion that the plants are derived one
way and the birds another?
I certainly did take it for granted that you supposed the stocking [by]
occasional transport to be something even more than a "well-established
hypothesis," but disputants seldom stop to measure the strength of their
I shall be with you on Saturday week, I hope. I should have come before,
but have made so little progress that I could not. I am now at St. Helena,
and shall then go to, and finish with, Kerguelen's land.
(371/1. After giving the distances of the Azores, etc., from America, Sir
But to my mind [it] does not mend the matter--for I do not ask why Azores
have even proportionally (to distance) a smaller number of American plants,
but why they have none, seeing the winds and currents set that way. The
Bermudas are all American in flora, but from what Col. Munro informs me I
should say they have nothing but common American weeds and the juniper
(cedar). No changed forms, yet they are as far from America as Azores from
Europe. I suppose they are modern and out of the pale.
...There is this, to me, astounding difference between certain oceanic
islands which were stocked by continental extension and those stocked by
immigration (following in both definitions your opinion), that the former
[continental] do contain many types of the more distant continent, the
latter do not any! Take Madagascar, with its many Asiatic genera unknown
in Africa; Ceylon, with many Malayan types not Peninsular; Japan, with many
non-Asiatic American types. Baird's fact of Greenland migration I was
aware of since I wrote my Arctic paper. I wish I was as satisfied either
of continental [extensions] or of transport means as I am of my Greenland
Oh, dear me, what a comfort it is to have a belief (sneer away).
LETTER 372. J.D. HOOKER TO CHARLES DARWIN.
Kew, December 4th, 1866.
I have just finished the New Zealand "Manual" (372/1. "Handbook of the New
Zealand Flora."), and am thinking about a discussion on the geographical
distribution, etc., of the plants. There is scarcely a single indigenous
annual plant in the group. I wish that I knew more of the past condition
of the islands, and whether they have been rising or sinking. There is
much that suggests the idea that the islands were once connected during a
warmer epoch, were afterwards separated and much reduced in area to what
they now are, and lastly have assumed their present size. The remarkable
general uniformity of the flora, even of the arboreous flora, throughout so
many degrees of latitude, is a very remarkable feature, as is the
representation of a good many of the southern half of certain species of
the north, by very closely allied varieties or species; and, lastly, there
is the immense preponderance of certain genera whose species all run into
one another and vary horribly, and which suggest a rising area. I hear
that a whale has been found some miles inland.
LETTER 373. J.D. HOOKER TO CHARLES DARWIN.
Kew, December 14th, 1866.
I do not see how the mountains of New Zealand, S. Australia, and Tasmania
could have been peopled, and [with] so large an extent of antarctic (373/1.
"Introductory Essay to Flora of New Zealand," page xx. "The plants of the
Antarctic islands, which are equally natives of New Zealand, Tasmania, and
Australia, are almost invariably found only on the lofty mountains of these
countries.") forms common to Fuegia, without some intercommunication. And
I have always supposed this was before the immigration of Asiatic plants
into Australia, and of which plants the temperate and tropical plants of
that country may be considered as altered forms. The presence of so many
of these temperate and cold Australian and New Zealand genera on the top of
Kini Balu in Borneo (under the equator) is an awful staggerer, and demands
a very extended northern distribution of Australian temperate forms. It is
a frightful assumption that the plains of Borneo were covered with a
temperate cold vegetation that was driven up Kini Balu by the returning
cold. Then there is the very distant distribution of a few Australian
types northward to the Philippines, China, and Japan: that is a fearful
and wonderful fact, though, as these plants are New Zealand too for the
most part, the migration northward may have been east of Australia.
LETTER 374. TO J.D. HOOKER.
December 24th .
...One word more about the flora derived from supposed Pleistocene
antarctic land requiring land intercommunication. This will depend much,
as it seems to me, upon how far you finally settle whether Azores, Cape de
Verdes, Tristan d'Acunha, Galapagos, Juan Fernandez, etc., etc., etc., have
all had land intercommunication. If you do not think this necessary, might
not New Zealand, etc., have been stocked during commencing Glacial period
by occasional means from antarctic land? As for lowlands of Borneo being
tenanted by a moderate number of temperate forms during the Glacial period,
so far [is it] from appearing a "frightful assumption" that I am arrived at
that pitch of bigotry that I look at it as proved!
LETTER 375. J.D. HOOKER TO CHARLES DARWIN.
Kew, December 25th, 1866.
I was about to write to-day, when your jolly letter came this morning, to
tell you that after carefully going over the N.Z. Flora, I find that there
are only about thirty reputed indigenous Dicot. annuals, of which almost
half, not being found by Banks and Solander, are probably non-indigenous.
This is just 1/20th of the Dicots., or, excluding the doubtful, about
1/40th, whereas the British proportion of annuals is 1/4.6 amongst
Dicots.!!! Of the naturalised New Zealand plants one-half are annual! I
suppose there can be no doubt but that a deciduous-leaved vegetation
affords more conditions for vegetable life than an evergreen one, and that
it is hence that we find countries characterised by uniform climates to be
poor in species, and those to be evergreens. I can now work this point out
for New Zealand and Britain. Japan may be an exception: it is an
extraordinary evergreen country, and has many species apparently, but it
has so much novelty that it may not be so rich in species really as it
hence looks, and I do believe it is very poor. It has very few annuals.
Then, again, I think that the number of plants with irregular flowers, and
especially such as require insect agency, diminishes much with
evergreenity. Hence in all humid temperate regions we have, as a rule, few
species, many evergreens, few annuals, few Leguminosae and orchids, few
lepidoptera and other flying insects, many Coniferae, Amentaceae,
Gramineae, Cyperaceae, and other wind-fertilised trees and plants, etc.
Orchids and Leguminosae are scarce in islets, because the necessary
fertilising insects have not migrated with the plants. Perhaps you have
LETTER 376. TO J.D. HOOKER.
Down, January 9th .
I like the first part of your paper in the "Gard. Chronicle" (376/1. The
lecture on Insular Floras ("Gard. Chron." January 1867).) to an
extraordinary degree: you never, in my opinion, wrote anything better.
You ask for all, even minute criticisms. In the first column you speak of
no alpine plants and no replacement by zones, which will strike every one
with astonishment who has read Humboldt and Webb on Zones on Teneriffe. Do
you not mean boreal or arctic plants? (376/2. The passage which seems to
be referred to does mention the absence of BOREAL plants.) In the third
column you speak as if savages (376/3. "Such plants on oceanic islands
are, like the savages which in some islands have been so long the sole
witnesses of their existence, the last representatives of their several
races.") had generally viewed the endemic plants of the Atlantic islands.
Now, as you well know, the Canaries alone of all the archipelagoes were
inhabited. In the third column have you really materials to speak of
confirming the proportion of winged and wingless insects on islands?
Your comparison of plants of Madeira with islets of Great Britain is
admirable. (376/4. "What should we say, for instance, if a plant so
totally unlike anything British as the Monizia edulis...were found on one
rocky islet of the Scillies, or another umbelliferous plant,
Melanoselinum...on one mountain in Wales; or if the Isle of Wight and
Scilly Islands had varieties, species, and genera too, differing from
anything in Britain, and found nowhere else in the world!")
I must allude to one of your last notes with very curious case of
proportion of annuals in New Zealand. (376/5. On this subject see
Hildebrand's interesting paper "Die Lebensdauer der Pflanzen" (Engler's
"Botanische Jahrbucher," Volume II., 1882, page 51). He shows that annuals
are rare in very dry desert-lands, in northern and alpine regions. The
following table gives the percentages of annuals, etc., in various
situations in Freiburg (Baden):--
Annuals. Biennials. Perennials. Trees and
Sandy, dry, and
stony places: 21 11 65 3
Dry fields: 6 4 90
Damp fields: 12 2 77 9
Woods and copses: 3 2 65 31
Water: 3 97
Cultivated land: 89 11)
Are annuals adapted for short seasons, as in arctic regions, or tropical
countries with dry season, or for periodically disturbed and cultivated
ground? You speak of evergreen vegetation as leading to few or confined
conditions; but is not evergreen vegetation connected with humid and
equable climate? Does not a very humid climate almost imply (Tyndall) an
I have never printed a word that I can remember about orchids and
papilionaceous plants being few in islands on account of rarity of insects;
and I remember you screamed at me when I suggested this a propos of
Papilionaceae in New Zealand, and of the statement about clover not seeding
there till the hive-bee was introduced, as I stated in my paper in "Gard.
Chronicle." (376/6. "In an old number of the "Gardeners' Chronicle" an
extract is given from a New Zealand newspaper in which much surprise is
expressed that the introduced clover never seeded freely until the hive-bee
was introduced." "On the Agency of Bees in the Fertilisation of
Papilionaceous Flowers..." ("Gard. Chron." 1858, page 828). See Letter
362, note.) I have been these last few days vexed and annoyed to a foolish
degree by hearing that my MS. on Domestic Animals, etc., will make two
volumes, both bigger than the "Origin." The volumes will have to be
full-sized octavo, so I have written to Murray to suggest details to be
printed in small type. But I feel that the size is quite ludicrous in
relation to the subject. I am ready to swear at myself and at every fool
who writes a book.
LETTER 377. TO J.D. HOOKER.
Down, January 15th .
Thanks for your jolly letter. I have read your second article (377/1. The
lecture on Insular Floras was published in instalments in the "Gardeners'
Chronicle," January 5th, 12th, 19th, 26th, 1867.), and like it even more
than the first, and more than this I cannot say. By mere chance I stumbled
yesterday on a passage in Humboldt that a violet grows on the Peak of
Teneriffe in common with the Pyrenees. If Humboldt is right that the
Canary Is. which lie nearest to the continent have a much stronger African
character than the others, ought you not just to allude to this? I do not
know whether you admit, and if so allude to, the view which seems to me
probable, that most of the genera confined to the Atlantic islands (I do
not say the species) originally existed in, and were derived from, Europe,
[and have] become extinct on this continent. I should thus account for the
community of peculiar genera in the several Atlantic islands. About the
Salvages is capital. (377/2. The Salvages are rocky islets about midway
between Madeira and the Canaries; and they have an Atlantic flora, instead
of, as might have been expected, one composed of African immigrants.
("Insular Floras," page 5 of separate copy.)) I am glad you speak of
LINKING, though this sounds a little too close, instead of being
continuous. All about St. Helena is grand. You have no faith, but if I
knew any one who lived in St. Helena I would supplicate him to send me home
a cask or two of earth from a few inches beneath the surface from the upper
part of the island, and from any dried-up pond, and thus, as sure as I'm a
wriggler, I should receive a multitude of lost plants.
I did suggest to you to work out proportion of plants with irregular
flowers on islands; I did this after giving a very short discussion on
irregular flowers in my Lythrum paper. (377/3. "Linn. Soc. Journ." VIII.,
1865, page 169.) But what on earth has a mere suggestion like this to do
with meum and tuum? You have comforted me much about the bigness of my
book, which yet turns me sick when I think of it.