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More Letters of Charles Darwin Volume II by Charles Darwin

Part 9 out of 14

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I have just heard that some misfortune has befallen you, and that you
have been treated shamefully. (749/1. Hermann Muller was accused by
the Ultramontane party of introducing into his school-teaching crude
hypotheses ("unreife Hypothesen"), which were assumed to have a harmful
influence upon the religious sentiments of his pupils. Attempts were
made to bring about Muller's dismissal, but the active hostility of his
opponents, which he met in a dignified spirit, proved futile. ("Prof.
Dr. Hermann Muller von Lippstadt. Ein Gedenkblatt," von Ernst Krause.
"Kosmos," VII., page 393, 1883.)) I grieve deeply to hear this, and as
soon as you can find a few minutes to spare, I earnestly beg you to let
me hear what has happened.


(750/1. The following letters refer to two forms of wheat cultivated in
Russia under the names Kubanka and Saxonka, which had been sent to Mr.
Darwin by Dr. Asher from Samara, and were placed in the hands of Mr.
Wilson that he might test the belief prevalent in Russia that Kubanka
"grown repeatedly on inferior soil," assumes "the form of Saxonka." Mr.
Wilson's paper of 1880 gives the results of his inquiry. He concludes
(basing his views partly on analogous cases and partly on his study of
the Russian wheats) that the supposed transformation is explicable in
chief part by the greater fertility of the Saxonka wheat leading to
extermination of the other form. According to Mr. Wilson, therefore,
the Saxonka survivors are incorrectly assumed to be the result of the
conversion of one form into the other.)

Down, April 24th, 1878.

I send you herewith some specimens which may perhaps interest you, as
you have so carefully studied the varieties of wheat. Anyhow, they are
of no use to me, as I have neither knowledge nor time sufficient. They
were sent me by the Governor of the Province of Samara, in Russia, at
the request of Dr. Asher (son of the great Berlin publisher) who farmed
for some years in the province. The specimen marked Kubanka is a very
valuable kind, but which keeps true only when cultivated in fresh
steppe-land in Samara, and in Saratoff. After two years it degenerates
into the variety Saxonica, or its synonym Ghirca. The latter alone is
imported into this country. Dr. Asher says that it is universally
known, and he has himself witnessed the fact, that if grain of the
Kubanka is sown in the same steppe-land for more than two years it
changes into Saxonica. He has seen a field with parts still Kubanka and
the remainder Saxonica. On this account the Government, in letting
steppe-land, contracts that after two years wheat must not be sown until
an interval of eight years. The ears of the two kinds appear different,
as you will see, but the chief difference is in the quality of the
grains. Dr. Asher has witnessed sales of equal weights of Kubanka and
Saxonica grain, and the price of the former was to that of the latter as
7 to 4. The peasants say that the change commences in the terminal
grain of the ear. The most remarkable point, as Dr. Asher positively
asserts, is that there are no intermediate varieties; but that a grain
produces a plant yielding either true Kubanka or true Saxonica. He
thinks that it would be interesting to sow here both kinds in good and
bad wheat soil and observe the result. Should you think it worth while
to make any such trial, and should you require further information, Dr.
Asher, whose address I enclose, will be happy to give any in his power.

Basset, Southampton, April 29th [1878].

Your kind note and specimens have been forwarded to me here, where I am
staying at my son's house for a fortnight's complete rest, which I
required from rather too hard work. For this reason I will not now
examine the seeds, but will wait till returning home, when, with my son
Francis' aid, I will look to them.

I always felt, though without any good reason, rather sceptical about
Prof. Buckman's experiment, and I afterwards heard that a most wicked
and cruel trick had been played on him by some of the agricultural
students at Cirencester, who had sown seeds unknown to him in his
experimental beds. Whether he ever knew this I did not hear.

I am exceedingly glad that you are willing to look into the Russian
wheat case. It may turn out a mare's nest, but I have often
incidentally observed curious facts when making what I call "a fool's

Down, March 5th, 1879.

I have just returned home after an absence of a week, and your letter
was not forwarded to me; I mention this to account for my apparent
discourtesy in not having sooner thanked you. You have worked out the
subject with admirable care and clearness, and your drawings are
beautiful. I suspected that there was some error in the Russian belief,
but I did not think of the explanation which you have almost proved to
be the true one. It is an extremely interesting instance of a more
fertile variety beating out a less fertile one, and, in this case, one
much more valuable to man. With respect to publication, I am at a loss
to advise you, for I live a secluded life and do not see many
periodicals, or hear what is done at the various societies. It seems to
me that your paper should be published in some agricultural journal; for
it is not simply scientific, and would therefore not be published by the
Linnean or Royal Societies.

Would the Royal Agricultural Society be a fitting place? Unfortunately
I am not a member, and could not myself present it. Unless you think of
some better journal, there is the "Agricultural Gazette": I have
occasionally suggested articles for publication to the editor (though
personally unknown to me) which he has always accepted.

Permit me again to thank you for the thorough manner in which you have
worked out this case; to kill an error is as good a service as, and
sometimes even better than, the establishing a new truth or fact.

Down, February 13th, 1880.

It was very kind of you to send me two numbers of the "Gardeners'
Chronicle" with your two articles, which I have read with much
interest. (753/1. "Gardeners' Chronicle," 1879, page 652; 1880, pages
108, 173.) You have quite convinced me, whatever Mr. Asher may say to
the contrary. I want to ask you a question, on the bare chance of your
being able to answer it, but if you cannot, please do not take the
trouble to write. The lateral branches of the silver fir often grow out
into knobs through the action of a fungus, Aecidium; and from these
knobs shoots grow vertically (753/2. The well-known "Witches-Brooms,"
or "Hexen-Besen," produced by the fungus Aecidium elatinum.) instead of
horizontally, like all the other twigs on the same branch. Now the
roots of Cruciferae and probably other plants are said to become knobbed
through the action of a fungus: now, do these knobs give rise to
rootlets? and, if so, do they grow in a new or abnormal direction?
(753/3. The parasite is probably Plasmodiophora: in this case no
abnormal rootlets have been observed, as far as we know.)

Down, June 18th, 1879.

The plants arrived last night in first-rate order, and it was very very
good of you to take so much trouble as to hunt them up yourself. They
seem exactly what I wanted, and if I fail it will not be for want of
perfect materials. But a confounded painter (I beg his pardon) comes
here to-night, and for the next two days I shall be half dead with
sitting to him; but after then I will begin to work at the plants and
see what I can do, and very curious I am about the results.

I have to thank you for two very interesting letters. I am delighted to
hear, and with surprise, that you care about old Erasmus D. God only
knows what I shall make of his life--it is such new kind of work to me.
(754/1. "Erasmus Darwin." By Ernst Krause. Translated from the German
by W.S. Dallas: with a preliminary notice by Charles Darwin. London,
1879. See "Life and Letters," III., pages 218-20.)

Thanks for case of sleeping Crotalaria--new to me. I quite agree to
every word you say about Ball's lecture (754/2. "On the Origin of the
Flora of the European Alps," "Geogr. Soc. Proc." Volume I., 1879, page
564. See Letter 395, Volume II.)--it is, as you say, like Sir W.
Thomson's meteorite. (754/3. In 1871 Lord Kelvin (Presidential Address
Brit. Assoc.) suggested that meteorites, "the moss-grown fragments from
the ruins of another world," might have introduced life to our planet.)
It is really a pity; it is enough to make Geographical Distribution
ridiculous in the eyes of the world. Frank will be interested about the
Auriculas; I never attended to this plant, for the powder did [not] seem
to me like true "bloom." (754/4. See Francis Darwin, on the relation
between "bloom" on leaves and the distribution of the stomata. "Linn.
Soc. Journ." Volume XXII., page 114.) This subject, however, for the
present only, has gone to the dogs with me.

I am sorry to hear of such a struggle for existence at Kew; but I have
often wondered how it is that you are all not killed outright.

I can most fully sympathise with you in your admiration of your little
girl. There is nothing so charming in this world, and we all in this
house humbly adore our grandchild, and think his little pimple of a nose
quite beautiful.

Down, February 16th, 1880.

I have had real pleasure in signing Dyer's certificate. (755/1. As a
candidate for the Royal Society.) It was very kind in you to write to
me about the Orchideae, for it has pleased me to an extreme degree that
I could have been of the least use to you about the nature of the parts.
They are wonderful creatures, these orchids, and I sometimes think with
a glow of pleasure, when I remember making out some little point in
their method of fertilisation. (755/2. Published in "Life and
Letters," III., page 288.) With respect to terms, no doubt you will be
able to improve them greatly, for I knew nothing about the terms as used
in other groups of plants. Could you not invent some quite new term for
gland, implying viscidity? or append some word to gland. I used for
cirripedes "cement gland."

Your present work must be frightfully difficult. I looked at a few
dried flowers, and could make neither heads nor tails of them; and I
well remember wondering what you would do with them when you came to the
group in the "Genera Plantarum." I heartily wish you safe through your

Down, September 4th, 1880.

I hope that you will not think me a great bore, but I have this minute
finished reading your address at the British Association; and it has
interested me so much that I cannot resist thanking you heartily for the
pleasure derived from it, not to mention the honour which you have done
me. (756/1. Presidential address delivered by Prof. F.M. Balfour
before the Biological Section at the British Association meeting at
Swansea (1880).) The recent progress of embryology is indeed splendid.
I have been very stupid not to have hitherto read your book, but I have
had of late no spare time; I have now ordered it, and your address will
make it the more interesting to read, though I fear that my want of
knowledge will make parts unintelligible to me. (756/2. "A Treatise on
Comparative Embryology," 2 volumes. London, 1880.) In my recent work
on plants I have been astonished to find to how many very different
stimuli the same small part--viz., the tip of the radicle--is sensitive,
and has the power of transmitting some influence to the adjoining part
of the radicle, exciting it to bend to or from the source of irritation
according to the needs of the plant (756/3. See Letter 757.); and all
this takes place without any nervous system! I think that such facts
should be kept in mind when speculating on the genesis of the nervous
system. I always feel a malicious pleasure when a priori conclusions
are knocked on the head: and therefore I felt somewhat like a devil
when I read your remarks on Herbert Spencer (756/4. Prof. Balfour
discussed Mr. Herbert Spencer's views on the genesis of the nervous
system, and expressed the opinion that his hypothesis was not borne out
by recent discoveries. "The discovery that nerves have been developed
from processes of epithelial cells gives a very different conception of
their genesis to that of Herbert Spencer, which makes them originate
from the passage of nervous impulses through a track of mingled
colloids..." (loc. cit., page 644.))...Our recent visit to Cambridge was
a brilliant success to us all, and will ever be remembered by me with
much pleasure.


(757/1. During the closing years of his life, Darwin began to
experimentise on the possibility of producing galls artificially. A
letter to Sir J.D. Hooker (November 3rd, 1880) shows the interest which
he felt in the question:--

"I was delighted with Paget's essay (757/2. An address on "Elemental
Pathology," delivered before the British Medical Association, August
1880, and published in the Journal of the Association.); I hear that he
has occasionally attended to this subject from his youth...I am very
glad he has called attention to galls: this has always seemed to me a
profoundly interesting subject; and if I had been younger would take it

His interest in this subject was connected with his ever-present wish to
learn something of the causes of variation. He imagined to himself
wonderful galls caused to appear on the ovaries of plants, and by these
means he thought it possible that the seed might be influenced, and thus
new varieties arise. (757/3. There would have been great difficulties
about this line of research, for when the sexual organs of plants are
deformed by parasites (in the way he hoped to effect by poisons)
sterility almost always results. See Molliard's "Les Cecidies
Florales," "Ann. Sci. Nat." 1895, Volume I., page 228.) He made a
considerable number of experiments by injecting various reagents into
the tissues of leaves, and with some slight indications of success.
(757/4. The above passage is reprinted, with alterations, from "Life
and Letters," III., page 346.)

The following letter to the late Sir James Paget refers to the same

Down, November 14th, 1880.

I am very much obliged for your essay, which has interested me greatly.
What indomitable activity you have! It is a surprising thought that the
diseases of plants should illustrate human pathology. I have the German
"Encyclopaedia," and a few weeks ago told my son Francis that the
article on the diseases of plants would be well worth his study; but I
did not know it was written by Dr. Frank, for whom I entertain a high
respect as a first-rate observer and experimentiser, though for some
unknown reason he has been a good deal snubbed in Germany. I can give
you one good case of regrowth in plants, recently often observed by me,
though only externally, as I do not know enough of histology to follow
out details. It is the tip of the radicle of a germinating common bean.
The case is remarkable in some respects, for the tip is sensitive to
various stimuli, and transmits an order, causing the upper part of the
radicle to bend. When the tip (for a length of about 1 mm.) is cut
transversely off, the radicle is not acted on by gravitation or other
irritants, such as contact, etc., etc., but a new tip is regenerated in
from two to four days, and then the radicle is again acted on by
gravitation, and will bend to the centre of the earth. The tip of the
radicle is a kind of brain to the whole growing part of the radicle!
(757/5. We are indebted to Mr. Archer-Hind for the translation of the
following passage from Plato ("Timaeus," 90A): "The reason is every
man's guardian genius (daimon), and has its habitation in our brain; it
is this that raises man (who is a plant, not of earth but of heaven) to
an erect posture, suspending the head and root of us from the heavens,
which are the birthplace of our soul, and keeping all the body upright."
On the perceptions of plants, see "Nature," November 14th, 1901--a
lecture delivered at the Glasgow meeting of the British Association by
Francis Darwin. See also Bonitz, "Index Aristotelicus," S.V. phuton.)

My observation will be published in about a week's time, and I would
have sent you the book, but I do not suppose that there is anything else
in the book which would interest you. I am delighted that you have
drawn attention to galls. They have always seemed to me profoundly
interesting. Many years ago I began (but failed for want of time,
strength, and health, as on infinitely many other occasions) to
experimentise on plants, by injecting into their tissues some alkaloids
and the poison of wasps, to see if I could make anything like galls. If
I remember rightly, in a few cases the tissues were thickened and
hardened. I began these experiments because if by different poisons I
could have affected slightly and differently the tissues of the same
plant, I thought there would be no insuperable difficulty in the fittest
poisons being developed by insects so as to produce galls adapted for
them. Every character, as far as I can see, is apt to vary. Judging
from one of your sentences you will smile at this.

To any one believing in my pangenesis (if such a man exists) there does
not seem to me any extreme difficulty in understanding why plants have
such little power of regeneration; for there is reason to think that my
imaginary gemmules have small power of passing from cell to cell.
(757/6. On regeneration after injury, see Massart, "La Cicatrisation
chez les Vegetaux," in Volume 57 (1898) of the "Memoires Couronnes,"
published by the Royal Academy of Belgium. An account of the literature
is given by the author.)

Forgive me for scribbling at such unreasonable length; but you are to
blame for having interested me so much.

P.S.--Perhaps you may remember that some two years ago you asked me to
lunch with you, and proposed that I should offer myself again. Whenever
I next come to London, I will do so, and thus have the pleasure of
seeing you.


(758/1. "The Power of Movement in Plants" was published early in
November, 1880. Sir W. Thiselton-Dyer, in writing to thank Darwin for a
copy of the book, had (November 20th) compared a structure in the
seedling Welwitschia with the "peg" of Cucurbita (see "Power of
Movement," page 102). Dyer wrote: "One peculiar feature in the
germinating embryo is a lateral hypocotyledonary process, which
eventually serves as an absorbent organ, by which the nutriment of the
endosperm is conveyed to the seedling. Such a structure was quite new
to me, and Bower and I were disposed to see in it a representative of
the foot in Selaginella, when I saw the account of Flahault's 'peg.'"
Flahault, it should be explained, was the discoverer of the curious peg
in Cucurbita. Prof. Bower wrote a paper ("On the Germination and
Histology of the seedling of Welwitschia mirabilis" in the "Quart.
Journ. Microscop. Sci." XXI., 1881, page 15.)

Down, November 28th [1880].

Very many thanks for your most kind note, but you think too highly of
our work--not but what this is very pleasant.

I am deeply interested about Welwitschia. When at work on the pegs or
projections I could not imagine how they were first developed, before
they could have been of mere mechanical use. Now it seems possible that
a circle between radicle and hypocotyl may be permeable to fluids, and
thus have given rise to projections so as to expose larger surface.
Could you test Welwitschia with permanganate of potassium: if, like my
pegs, the lower surface would be coloured brown like radicle, and upper
surface left white like hypocotyl. If such an idea as yours, of an
absorbing organ, had ever crossed my mind, I would have tried many
hypocotyls in weak citrate of ammonia, to see if it penetrated on line
of junction more easily than elsewhere. I daresay the projection in
Abronia and Mirabilis may be an absorbent organ. It was very good fun
bothering the seeds of Cucurbita by planting them edgeways, as would
never naturally occur, and then the peg could not act properly. Many of
the Germans are very contemptuous about making out use of organs; but
they may sneer the souls out of their bodies, and I for one shall think
it the most interesting part of natural history. Indeed, you are
greatly mistaken if you doubt for one moment on the very great value of
your constant and most kind assistance to us. I have not seen the
pamphlet, and shall be very glad to keep it. Frank, when he comes home,
will be much interested and pleased with your letter. Pray give my
kindest remembrance to Mrs. Dyer.

This is a very untidy note, but I am very tired with dissecting worms
all day. Read the last chapter of our book, and then you will know the
whole contents.

Down, December 16th, 1880.

Absence from home has prevented me from sooner thanking you for your
kind present of your several publications. I procured some time ago
your "Organbilding" (759/1. "Organbildung im Pflanzenreich," 1878.)
etc., but it was too late for me to profit by it for my book, as I was
correcting the press. I read only parts, but my son Francis read the
whole with care and told me much about it, which greatly interested me.
I also read your article in the "Bot. Zeitung." My son began at once
experimenting, to test your views, and this very night will read a paper
before the Linnean Society on the roots of Rubus (759/2. Francis
Darwin, "The Theory of the Growth of Cuttings" ("Linn. Soc. Journ."
XVIII.). [I take this opportunity of expressing my regret that at page
417, owing to neglect of part of Vochting's facts, I made a criticism of
his argument which cannot be upheld.--F.D.].), and I think that you will
be pleased to find how well his conclusions agree with yours. He will
of course send you a copy of his paper when it is printed. I have sent
him your letter, which will please him if he agrees with me; for your
letter has given me real pleasure, and I did not at all know what the
many great physiologists of Germany, Switzerland, and Holland would
think of it ["The Power of Movement," etc.]. I was quite sorry to read
Sachs' views about root-forming matter, etc., for I have an unbounded
admiration for Sachs. In this country we are dreadfully behind in
Physiological Botany.

Down, January 24th, 1881.

It was extremely kind of you to write me so long and valuable a letter,
the whole of which deserves careful consideration. I have been
particularly pleased at what you say about the new terms used, because I
have often been annoyed at the multitude of new terms lately invented in
all branches of Biology in Germany; and I doubted much whether I was not
quite as great a sinner as those whom I have blamed. When I read your
remarks on the word "purpose" in your "Phytographie," I vowed that I
would not use it again; but it is not easy to cure oneself of a vicious
habit. It is also difficult for any one who tries to make out the use
of a structure to avoid the word purpose. I see that I have probably
gone beyond my depth in discussing plurifoliate and unifoliate leaves;
but in such a case as that of Mimosa albida, where rudiments of
additional leaflets are present, we must believe that they were well
developed in the progenitor of the plant. So again, when the first true
leaf differs widely in shape from the older leaves, and resembles the
older leaves in allied species, is it not the most simple explanation
that such leaves have retained their ancient character, as in the case
of the embryos of so many animals?

Your suggestion of examining the movements of vertical leaves with an
equal number of stomata on both sides, with reference to the light,
seems to me an excellent one, and I hope that my son Francis may follow
it up. But I will not trouble you with any more remarks about our book.
My son will write to you about the diagram.

Let me add that I shall ever remember with pleasure your visit here last

LETTER 761. TO J. LUBBOCK (Lord Avebury).
Down, April 16th [1881].

Will you be so kind as to send and lend me the Desmodium gyrans by the
bearer who brings this note.

Shortly after you left I found my notice of the seeds in the "Gardeners'
Chronicle," which please return hereafter, as I have no other copy.
(761/1. "Note on the Achenia of Pumilio argyrolepis." "Gardeners'
Chronicle," 1861, page 4.) I do not think that I made enough about the
great power of absorption of water by the corolla-like calyx or pappus.
It seems to me not unlikely that the pappus of other Compositae may be
serviceable to the seeds, whilst lying on the ground, by absorbing the
dew which would be especially apt to condense on the fine points and
filaments of the pappus. Anyhow, this is a point which might be easily
investigated. Seeds of Tussilago, or groundsel (761/2. It is not clear
whether Tussilago or groundsel (Senecio vulgaris) is meant; or whether
he was not sure which of the two plants becomes slimy when wetted.),
emit worm-like masses of mucus, and it would be curious to ascertain
whether wetting the pappus alone would suffice to cause such secretion.
(761/3. See Letter 707.)

Down, April 18th, 1881.

I am extremely glad of your success with the flashing light. (762/1.
Romanes' paper on the effect of intermittent light on heliotropism was
the "Proc. Royal Soc." Volume LIV., page 333.) If plants are acted on
by light, like some of the lower animals, there is an additional point
of interest, as it seems to me, in your results. Most botanists believe
that light causes a plant to bend to it in as direct a manner as light
affects nitrate of silver. I believe that it merely tells the plant to
which side to bend, and I see indications of this belief prevailing even
with Sachs. Now it might be expected that light would act on a plant in
something the same manner as on the lower animals. As you are at work
on this subject, I will call your attention to another point. Wiesner,
of Vienna (who has lately published a great book on heliotropism) finds
that an intermittent light, say of 20 minutes, produces the same effect
as a continuous light of, say 60 m. (762/2. Wiesner's papers on
heliotropism are in the "Denkschriften" of the Vienna Academy, Volumes
39 and 43.) So that Van Tieghem, in the first part of his book which
has just appeared, remarks, the light during 40 m. out of the 60 m.
produced no effect. I observed an analogous case described in my book.
(762/3. "Power of Movement," page 459.)

Wiesner and Van Tieghem seem to think that this is explained by calling
the whole process "induction," borrowing a term used by some physico-
chemists (of whom I believe Roscoe is one) and implying an agency which
does not produce any effect for some time, and continues its effect for
some time after the cause has ceased. I believe that photographic paper
is an instance. I must ask Leonard (762/4. Mr. Darwin's son.) whether
an interrupted light acts on it in the same manner as on a plant. At
present I must still believe in my explanation that it is the contrast
between light and darkness which excites a plant.

I have forgotten my main object in writing--viz., to say that I believe
(and have so stated) that seedlings vary much in their sensitiveness to
light; but I did not prove this, for there are many difficulties,
whether the time of incipient curvature or the amount of curvature is
taken as the criterion. Moreover they vary according to age, and
perhaps from vigour of growth, and there seems inherent variability, as
Strasburger (whom I quote) found with spores. If the curious anomaly
observed by you is due to varying sensitiveness, ought not all the
seedlings to bend if the flashes were at longer intervals of time?
According to my notion of contrast between light and darkness being the
stimulus, I should expect that if flashes were made sufficiently slow it
would be a powerful stimulus, and that you would suddenly arrive at a
period when the result would SUDDENLY become great. On the other hand,
as far as my experience goes, what one expects rarely happens.

Down, October 4th, 1881.

I thank you sincerely for your very kind letter, and for the present of
your new work. (763/1. "Das Bewegungsvermogen der Pflanze," 1881. One
of us has given some account of Wiesner's book in the presidential
address to Section D of the British Association, 1891. Wiesner's
divergence from Darwin's views is far-reaching, and includes the main
thesis of the "Power of Movement." See "Life and Letters," III., page
336, for an interesting letter to Wiesner.) My son Francis, if he had
been at home, would have likewise sent his thanks. I will immediately
begin to read your book, and when I have finished it will write again.
But I read german so very slowly that your book will take me a
considerable time, for I cannot read for more than half an hour each
day. I have, also, been working too hard lately, and with very little
success, so that I am going to leave home for a time and try to forget

I quite expect that you will find some gross errors in my work, for you
are a very much more skilful and profound experimentalist than I am.
Although I always am endeavouring to be cautious and to mistrust myself,
yet I know well how apt I am to make blunders. Physiology, both animal
and vegetable, is so difficult a subject, that it seems to me to
progress chiefly by the elimination or correction of ever-recurring
mistakes. I hope that you will not have upset my fundamental notion
that various classes of movement result from the modification of a
universally present movement of circumnutation.

I am very glad that you will again discuss the view of the turgescence
of the cells being the cause of the movement of parts. I adopted De
Vries' views as seeming to me the most probable, but of late I have felt
more doubts on this head. (763/2. See "Power of Movement," page 2. De
Vries' work is published in the "Bot. Zeitung," 1879, page 830.)

Glenrhydding House, Patterdale, Penrith, June 15th, 1881.

It was real pleasure to me to see once again your well-known handwriting
on the outside of your note. I do not know how long you have returned
from Italy, but I am very sorry that you are so bothered already with
work and visits. I cannot but think that you are too kind and civil to
visitors, and too conscientious about your official work. But a man
cannot cure his virtues, any more than his vices, after early youth; so
you must bear your burthen. It is, however, a great misfortune for
science that you have so very little spare time for the "Genera." I can
well believe what an awful job the palms must be. Even their size must
be very inconvenient. You and Bentham must hate the monocotyledons, for
what work the Orchideae must have been, and Gramineae and Cyperaceae
will be. I am rather despondent about myself, and my troubles are of an
exactly opposite nature to yours, for idleness is downright misery to
me, as I find here, as I cannot forget my discomfort for an hour. I
have not the heart or strength at my age to begin any investigation
lasting years, which is the only thing which I enjoy; and I have no
little jobs which I can do. So I must look forward to Down graveyard as
the sweetest place on earth. This place is magnificently beautiful, and
I enjoy the scenery, though weary of it; and the weather has been very
cold and almost always hazy.

I am so glad that your tour has answered for Lady Hooker. We return
home on the first week of July, and should be truly glad to aid Lady
Hooker in any possible manner which she will suggest.

I have written to my gardener to send you plants of Oxalis corniculata
(and seeds if possible). I should think so common a weed was never
asked for before,--and what a poor return for the hundreds of plants
which I have received from Kew! I hope that I have not bothered you by
writing so long a note, and I did not intend to do so.

If Asa Gray has returned with you, please give him my kindest

October 22nd, 1881.

I am investigating the action of carbonate of ammonia on chlorophyll,
which makes me want the plants in my list. (765/1. "The Action of
Carbonate of Ammonia on Chlorophyll Bodies." "Linn. Soc. Journ." XIX.,
page 262, 1882.) I have incidentally observed one point in Euphorbia,
which has astonished me--viz. that in the fine fibrous roots of
Euphorbia, the alternate rows of cells in their roots must differ
physiologically, though not in external appearance, as their contents
after the action of carbonate of ammonia differ most conspicuously...

Wiesner of Vienna has just published a book vivisecting me in the most
courteous, but awful manner, about the "Power of Movement in Plants."
(765/2. See Letter 763, note.) Thank heaven, he admits almost all my
facts, after re-trying all my experiments; but gives widely different
interpretation of the facts. I think he proves me wrong in several
cases, but I am convinced that he is utterly erroneous and fanciful in
other explanations. No man was ever vivisected in so sweet a manner
before, as I am in this book.



2.XII.I. VIVISECTION, 1875-1882.


(766/1. A Bill was introduced to the House of Commons by Messrs. Lyon
Playfair, Walpole and Ashley, in the spring of 1875, but was withdrawn
on the appointment of a Royal Commission to inquire into the whole
question. Some account of the Anti-Vivisection agitation, the
introduction of bills, and the appointment of a Royal Commission is
given in the "Life and Letters," III., page 201, where the more
interesting of Darwin's letters on the question are published.)

Down, May 26th, 1875.

I hope that you will excuse my troubling you once again. I received
some days ago a letter from Prof. Huxley, in Edinburgh, who says with
respect to your Bill: "the professors here are all in arms about it,
and as the papers have associated my name with the Bill, I shall have to
repudiate it publicly, unless something can be done. But what in the
world is to be done?" (766/2. The letter is published in full in Mr.
L. Huxley's interesting chapter on the vivisection question in his
father's "Life," I., page 438.) Dr. Burdon Sanderson is in nearly the
same frame of mind about it. The newspapers take different views of the
purport of the Bill, but it seems generally supposed that it would
prevent demonstrations on animals rendered insensible, and this seems to
me a monstrous provision. It would, moreover, probably defeat the end
desired; for Dr. B. Sanderson, who demonstrates to his class on animals
rendered insensible, told me that some of his students had declared to
him that unless he had shown them what he had, they would have
experimented on live animals for themselves. Certainly I do not believe
that any one could thoroughly understand the action of the heart without
having seen it in action. I do not doubt that you wish to aid the
progress of Physiology, and at the same time save animals from all
useless suffering; and in this case I believe that you could not do a
greater service than to warn the Home Secretary with respect to the
appointment of Royal Commissioners, that ordinary doctors know little or
nothing about Physiology as a science, and are incompetent to judge of
its high importance and of the probability of its hereafter conferring
great benefits on mankind.

Down, May 28th.

I must write one line to thank you for your very kind letter, and to say
that, after despatching my last note, it suddenly occurred to me that I
had been rude in calling one of the provisions of your Bill "monstrous"
or "absurd"--I forget which. But when I wrote the expression it was
addressed to the bigots who, I believed, had forced you to a compromise.
I cannot understand what Dr. B. Sanderson could have been about not to
have objected with respect to the clause of not demonstrating on animals
rendered insensible. I am extremely sorry that you have had trouble and
vexation on the subject. It is a most disagreeable and difficult one.
I am not personally concerned, as I never tried an experiment on a
living animal, nor am I a physiologist; but I know enough to see how
ruinous it would be to stop all progress in so grand a science as
Physiology. I commenced the agitation amongst the physiologists for
this reason, and because I have long felt very keenly on the question of
useless vivisection, and believed, though without any good evidence,
that there was not always, even in this country, care enough taken.
Pray forgive me this note, so much about myself...


(768/1. Published in "Life of Romanes," page 61, under 1876-77.)

Down, June 4th [1876].

Your letter has made me as proud and conceited as ten peacocks. (768/2.
This may perhaps refer to Darwin being elected the only honorary member
of the Physiological Society, a fact that was announced in a letter from
Romanes June 1st, 1876, published in the "Life" of Romanes, page 50.
Dr. Sharpey was subsequently elected a second honorary member.) I am
inclined to think that writing against the bigots about vivisection is
as hopeless as stemming a torrent with a reed. Frank, who has just come
here, and who sputters with indignation on the subject, takes an
opposite line, and perhaps he is right; anyhow, he had the best of an
argument with me on the subject...It seems to me the physiologists are
now in the position of a persecuted religious sect, and they must grin
and bear the persecution, however cruel and unjust, as well as they can.


(769/1. In November, 1881, an absolutely groundless charge was brought
by the Victoria Street Society for the Protection of Animals from
Vivisection against Dr. Ferrier for an infringement of the Vivisection
Act. The experiment complained of was the removal of the brain of a
monkey and the subsequent testing of the animal's powers of reacting to
certain treatment. The fact that the operation had been performed six
months before the case came into court would alone have been fatal to
the prosecution. Moreover, it was not performed by Dr. Ferrier, but by
another observer, who was licensed under the Act to keep the monkey
alive after the operation, which was performed under anaesthetics. Thus
the prosecution completely broke down, and the case was dismissed.
(769/2. From the "British Medical Journal," November 19th, 1881. See
also "Times," November 18th, 1881.) The sympathy with Dr. Ferrier in
the purely scientific and medical world was very strong, and the British
Medical Association undertook the defence. The prosecution did good in
one respect, inasmuch as it led to the formation of the Science Defence
Association, to which reference is made in some of Mr. Darwin's letters
to Sir Lauder Brunton. The Association still exists, and continues to
do good work.

Part of the following letter was published in the "British Medical
Journal," December 3rd, 1881.)

Down, November 19th, 1881.

I saw in some paper that there would probably be a subscription to pay
Dr. Ferrier's legal expenses in the late absurd and wicked prosecution.
As I live so retired I might not hear of the subscription, and I should
regret beyond measure not to have the pleasure and honour of showing my
sympathy [with] and admiration of Dr. Ferrier's researches. I know that
you are his friend, as I once met him at your house; so I earnestly beg
you to let me hear if there is any means of subscribing, as I should
much like to be an early subscriber. I am sure that you will forgive me
for troubling you under these circumstances.

P.S.--I finished reading a few days ago the several physiological and
medical papers which you were so kind as to send me. (769/3. Some of
Lauder Brunton's publications.) I was much interested by several of
them, especially by that on night-sweating, and almost more by others on
digestion. I have seldom been made to realise more vividly the wondrous
complexity of our whole system. How any one of us keeps alive for a day
is a marvel!

50, Welbeck Street, London, November 21st, 1881.

I thank you most sincerely for your kind letter and your offer of
assistance to Dr. Ferrier. There is at present no subscription list, as
the British Medical Association have taken up the case, and ought to pay
the expenses. Should these make such a call upon the funds of the
Association as to interfere with its other objects, the whole or part of
the expenses will be paid by those who have subscribed to a guarantee
fund. To this fund there are already a number of subscribers, whose
names are taken by Professor Gerald Yeo, one of the secretaries of the
Physiological Society. They have not subscribed a definite sum, but
have simply fixed a maximum which they will subscribe, if necessary, on
the understanding that only so much as is required shall be asked from
each subscriber in proportion to his subscription. It is proposed to
send by-and-by a list of the most prominent members of this guarantee
fund to the "Times" and other papers, and not only every scientific man,
but every member of the medical profession, will rejoice to see your
name in the list. Dr. Ferrier has been quite worn out by the worry of
this prosecution, or, as it might well be called, persecution, and has
gone down to Shanklin for a couple of days. He returns this afternoon,
and I have sent on your letter to await his arrival, knowing as I do
that it will be to him like cold water to a thirsty soul.

Down, November 22nd, 1881.

Many thanks for your very kind and interesting letter...

I write now to beg a favour. I do not in the least know what others
have guaranteed in relation to Dr. Ferrier. (771/1. In a letter dated
November 27th, 1881, Sir Lauder Brunton wrote in reply to Mr. Darwin's
inquiry as to the amount of the subscriptions: "When I ascertain what
they intend to give under the new conditions--viz., that the
subscriptions are not to be applied to Ferrier's defence, but to the
defence of others who may be attacked and to a diffusion of knowledge
regarding the nature and purposes of vivisection, I will let you
know...") Would twenty guineas be sufficient? If not, will you kindly
take the trouble to have my name put down for thirty or forty guineas,
as you may think best. If, on the other hand, no one else has
guaranteed for as much as twenty guineas, will you put me down for ten
or fifteen guineas, though I should like to give twenty best.

You can understand that I do not wish to be conspicuous either by too
little or too much; so I beg you to be so very kind as to act for me. I
have a multitude of letters which I must answer, so excuse haste.


(772/1. The following letter was written in reply to Sir T. Lauder
Brunton's suggestion that Mr. Darwin should be proposed as President of
the Science Defence Association.)

4, Bryanston Street, Portman Square, December 17th, 1881.

I have been thinking a good deal about the suggestion which you made to
me the other day, on the supposition that you could not get some man
like the President of the College of Physicians to accept the office.
My wife is strongly opposed to my accepting the office, as she feels
sure that the anxiety thus caused would tell heavily on my health. But
there is a much stronger objection suggested to me by one of my
relations--namely, no man ought to allow himself to be placed at the
head (though only nominally so) of an associated movement, unless he has
the means of judging of the acts performed by the association, after
hearing each point discussed. This occurred to me when you spoke to me,
and I think that I said something to this effect. Anyhow, I have in
several analogous cases acted on this principle.

Take, for instance, any preliminary statement which the Association may
publish. I might feel grave doubts about the wisdom or justice of some
points, and this solely from my not having heard them discussed. I am
therefore inclined to think that it would not be right in me to accept
the nominal Presidency of your Association, and thus have to act

As far as I can at present see, I fear that I must confine my assistance
to subscribing as large a sum to the Association as any member gives.

I am sorry to trouble you, but I have thought it best to tell you at
once of the doubts which have arisen in my mind.


(773/1. Sir T. Lauder Brunton had written (February 12th) to Mr. Darwin
explaining that two opinions were held as to the constitution of the
proposed Science Defence Association: one that it should consist of a
small number of representative men; the other that it should, if
possible, embrace every medical practitioner in the country. Sir Lauder
Brunton adds: "I should be very greatly obliged if you would kindly say
what you think of the two schemes.")

Down, February 14th, 1882.

I am very much obliged for your information in regard to the
Association, about which I feel a great interest. It seems to me highly
desirable that the Association should include as many medical and
scientific men as possible throughout the whole country, who could
illumine those capable of illumination on the necessity of physiological
research; but that the Association should be governed by a council of
powerful men, not too many in number. Such a council, as representing a
large body of medical men, would have more power in the eyes of vote-
hunting politicians than a small body representing only themselves.

From what I see of country practitioners, I think that their annual
subscription ought to be very small. But would it not be possible to
add to the rules some such statement as the following one: "That by a
donation of ... pounds, or of any larger sum, from those who feel a deep
interest in the progress of medical science, the donor shall become a
life member." I, for one, would gladly subscribe 50 or 100 pounds. If
such a plan were approved by the leading medical men of London, two or
three thousand pounds might at once be collected; and if any such sum
could be announced as already subscribed, when the program of the
Association is put forth, it would have, as I believe, a considerable
influence on the country, and would attract the attention of country
practitioners. The Anti-Corn Law League owed much of its enormous power
to several wealthy men laying down 1,000 pounds; for the subscription of
a good sum of money is the best proof of earnest conviction. You asked
for my opinion on the above points, and I have given it freely, though
well aware that from living so retired a life my judgment cannot be
worth much.

Have you read Mr. Gurney's articles in the "Fortnightly" and "Cornhill?"
(773/2. "Fortnightly Review," XXX., page 778; "Cornhill Magazine," XLV.,
page 191. The articles are by the late Edmund Gurney, author of "The
power of Sound," 1880.) They seem to me very clever, though obscurely
written; and I agree with almost everything he says, except with some
passages which appear to imply that no experiments should be tried
unless some immediate good can be predicted, and this is a gigantic
mistake contradicted by the whole history of science.

P.S.--That is a curious fact about babies. I remember hearing on good
authority that very young babies when moved are apt to clutch hold of
anything, and I thought of your explanation; but your case during sleep
is a much more interesting one. Very many thanks for the book, which I
much wanted to see; it shall be sent back to-day, as from you, to the



(774/1. The lecture which forms the subject of this letter was one
delivered by Canon Farrar at the Royal Institution, "On Some Defects in
Public School Education.")

Down, March 5th, 1867.

I am very much obliged for your kind present of your lecture. We have
read it aloud with the greatest interest, and I agree to every word. I
admire your candour and wonderful freedom from prejudice; for I feel an
inward conviction that if I had been a great classical scholar I should
never have been able to have judged fairly on the subject. As it is, I
am one of the root and branch men, and would leave classics to be learnt
by those alone who have sufficient zeal and the high taste requisite for
their appreciation. You have indeed done a great public service in
speaking out so boldly. Scientific men might rail forever, and it would
only be said that they railed at what they did not understand. I was at
school at Shrewsbury under a great scholar, Dr. Butler; I learnt
absolutely nothing, except by amusing myself by reading and
experimenting in chemistry. Dr. Butler somehow found this out, and
publicly sneered at me before the whole school for such gross waste of
time; I remember he called me a Pococurante (774/2. Told in "Life and
Letters," I., page 35.), which, not understanding, I thought was a
dreadful name. I wish you had shown in your lecture how science could
practically be taught in a great school; I have often heard it objected
that this could not be done, and I never knew what to say in answer.

I heartily hope that you may live to see your zeal and labour produce
good fruit.

Down, December 9th [1867].

I thank you very sincerely for your kind present of your "First
Principles." (775/1. "This must have been the second edition." (Note
by Mr. Spencer.)) I earnestly hope that before long I may have strength
to study the work as it ought to be studied, for I am certain to find or
re-find much that is deeply interesting. In many parts of your
"Principles of Biology" I was fairly astonished at the prodigality of
your original views. (775/2. See "Life and Letters," III., pages 55,
56.) Most of the chapters furnished suggestions for whole volumes of
future researches. As I have heard that you have changed your
residence, I am forced to address this to Messrs. Williams & Norgate;
and for the same reason I gave some time ago the same address to Mr.
Murray for a copy of my book on variation, etc., which is now finished,
but delayed by the index-maker.


(776/1. This letter refers to a movement set on foot at a meeting held
at the Freemasons' Tavern, on November 16th, 1872, of which an account
is given in the "Times" of November 23rd, 1872, at which Mark Pattison,
Mr. Henry Sidgwick, Sir Benjamin Brodie, Professors Rolleston, Seeley,
Huxley, etc., were present. The "Times" says that the meeting was held
"by members of the Universities and others interested in the promotion
of mature study and scientific research in England." One of the
headings of the "Program of Discussion" was "The Abolition of Prize

Sevenoaks, October 22nd [1872].

I have been glad to sign and forward the paper, for I have very long
thought it a sin that the immense funds of the Universities should be
wasted in Fellowships, except a few for paying for education. But when
I was at Cambridge it would have been an unjustifiable sneer to have
spoken of the place as one for education, always excepting the men who
went in for honours. You speak of another resolution "in the interest
of the anti-letter-writing association"--but alas, this never arrived!
I should like a society formed so that every one might receive pleasant
letters and never answer them.

We return home on Saturday, after three weeks of the most astounding
dullness, doing nothing and thinking of nothing. I hope my Brain likes
it--as for myself, it is dreadful doing nothing. (776/2. Darwin
returned to Down from Sevenoaks on Saturday, October 26th, 1872, which
fixes the date of the letter.)

Down, Saturday [1874?].

If you had called here after I had read the article you would have found
a much perplexed man. (777/1. Probably Sir W. Crookes' "Researches in
the Phenomena of Spiritualism" (reprinted from the "Quarterly Journal of
Science"), London, 1874. Other papers by Crookes are in the "Proceedings
of the Society for Psychical Research.") I cannot disbelieve Mr.
Crooke's statement, nor can I believe in his result. It has removed
some of my difficulty that the supposed power is not an anomaly, but is
common in a lesser degree to various persons. It is also a consolation
to reflect that gravity acts at any distance, in some wholly unknown
manner, and so may nerve-force. Nothing is so difficult to decide as
where to draw a just line between scepticism and credulity. It was a
very long time before scientific men would believe in the fall of
aerolites; and this was chiefly owing to so much bad evidence, as in the
present case, being mixed up with the good. All sorts of objects were
said to have been seen falling from the sky. I very much hope that a
number of men, such as Professor Stokes, will be induced to witness Mr.
Crooke's experiments.

(778/1. The two following extracts may be given in further illustration
of Darwin's guiding principle in weighing evidence. He wrote to Robert
Chambers, April 30th, 1861: "Thanks also for extract out of newspaper
about rooks and crows; I wish I dared trust it. I see in cutting the
pages [of Chambers' book, "Ice and Water"]...that you fulminate against
the scepticism of scientific men. You would not fulminate quite so much
if you had had so many wild-goose chases after facts stated by men not
trained to scientific accuracy. I often vow to myself that I will
utterly disregard every statement made by any one who has not shown the
world he can observe accurately." In a letter to Dr. Dohrn, of Naples,
January 4th, 1870, Darwin wrote: "Forgive me for suggesting one caution;
as Demosthenes said, 'Action, action, action,' was the soul of
eloquence, so is caution almost the soul of science.")

Down, July 16th, 1875.

Some little time ago Mr. Simon (778/1. Now Sir John Simon) sent me the
last Report, and your statements about contagion deeply interested me.
By the way, if you see Mr. Simon, and can remember it, will you thank
him for me; I was so busy at the time that I did not write. Having been
in correspondence with Paget lately on another subject, I mentioned to
him an analogy which has struck me much, now that we know that sheep-pox
is fungoid; and this analogy pleased him. It is that of fairy rings,
which are believed to spread from a centre, and when they intersect the
intersecting portion dies out, as the mycelium cannot grow where it has
grown during previous years. So, again, I have never seen a ring within
a ring; this seems to me a parallel case to a man commonly having the
smallpox only once. I imagine that in both cases the mycelium must
consume all the matter on which it can subsist.


(779/1. The following letter was written to the author (under the
pseudonym of Gapitche) of a pamphlet entitled "Quelques mots sur
l'Eternite du Corps Humaine" (Nice, 1880). Mr. Gapitche's idea was that
man might, by perfect adaptation to his surroundings, indefinitely
prolong the duration of life. We owe Mr. Darwin's letter to the
kindness of Herr Vetter, editor of the well-known journal "Kosmos.")

Down, February 24th, 1880.

I suppose that no one can prove that death is inevitable, but the
evidence in favour of this belief is overwhelmingly strong from the
evidence of all other living creatures. I do not believe that it is by
any means invariably true that the higher organisms always live longer
than the lower ones. Elephants, parrots, ravens, tortoises, and some
fish live longer than man. As evolution depends on a long succession of
generations, which implies death, it seems to me in the highest degree
improbable that man should cease to follow the general law of evolution,
and this would follow if he were to be immortal.

This is all that I can say.


(780/1. Mr. Popper had written about a proposed flying machine in which
birds were to take a part.)

Down, February 15th, 1881.

I am sorry to say that I cannot give you the least aid, as I have never
attended to any mechanical subjects. I should doubt whether it would be
possible to train birds to fly in a certain direction in a body, though
I am aware that they have been taught some tricks. Their mental powers
are probably much below those of mammals. It is said, and I suppose
truly, that an eagle will carry a lamb. This shows that a bird may have
great power for a short distance. I cannot remember your essay with
sufficient distinctness to make any remarks on it. When a man is old
and works hard, one subject drives another out of his head.

Worthing, September 9th, 1881.

(781/1. Mr. Anthony Rich left his house at Worthing as a legacy to Mr.
Huxley. See Huxley's "Life and Letters," II., pages 286, 287.)

We have been paying Mr. Rich a little visit, and he has often spoken of
you, and I think he enjoyed much your and Mrs. Huxley's visit here. But
my object in writing now is to tell you something, which I am very
doubtful whether it is worth while for you to hear, because it is
uncertain. My brother Erasmus has left me half his fortune, which is
very considerable. Therefore, I thought myself bound to tell Mr. Rich
of this, stating the large amount, as far as the executors as yet know
it roughly. I then added that my wife and self thought that, under
these new circumstances, he was most fully justified in altering his
will and leaving his property in some other way. I begged him to take a
week to consider what I had told him, and then by letter to inform me of
the result. But he would not, however, hardly allow me to finish what I
had to say, and expressed a firm determination not to alter his will,
adding that I had five sons to provide for. After a short pause he
implied (but unfortunately he here became very confused and forgot a
word, which on subsequent reflection I think was probably
"reversionary")--he implied that there was a chance, whether good or bad
I know not, of his becoming possessed of some other property, and he
finished by saying distinctly, "I will bequeath this to Huxley." What
the amount may be (I fear not large), and what the chance may be, God
only knows; and one cannot cross-examine a man about his will. He did
not bind me to secrecy, so I think I am justified in telling you what
passed, but whether it is wise on my part to send so vague a story, I am
not at all sure; but as a general rule it is best to tell everything.
As I know that you hate writing letters, do not trouble yourself to
answer this.

P.S.--On further reflection I should like to hear that you receive this
note safely. I have used up all my black-edged paper.

Down, February 4th, 1882.

It is always a pleasure to me to receive a letter from you. I am very
sorry to hear that you have been more troubled than usual with your old
complaint. Any one who looked at you would think that you had passed
through life with few evils, and yet you have had an unusual amount of
suffering. As a turnkey remarked in one of Dickens' novels, "Life is a
rum thing." (782/1. This we take to be an incorrect version of Mr.
Roker's remark (in reference to Tom Martin, the Butcher), "What a rum
thing Time is, ain't it, Neddy?" ("Pickwick," Chapter XLII.). A careful
student finds that women are also apostrophised as "rum": see the
remarks of the dirty-faced man ("Pickwick," Chapter XIV.).) As for
myself, I have been better than usual until about a fortnight ago, when
I had a cough, and this pulled me down and made me miserable to a
strange degree; but my dear old wife insisted on my taking quinine, and,
though I have very little faith in medicine, this, I think, has done me
much good. Well, we are both so old that we must expect some troubles:
I shall be seventy-three on Feb. 12th. I have been glad to hear about
the pine-leaves, and you are the first man who has confirmed my account
that they are drawn in by the base, with a very few exceptions. (782/2.
"The Formation of Vegetable Mould through the Action of Worms," 1881,
page 71.) With respect to your Wandsworth case, I think that if I had
heard of it before publishing, I would have said nothing about the
ledges (782/3. "Ledges of Earth on Steep Hill-sides" (ibid., page
278).); for the Grisedale case (782/4. "The steep, grass-covered sides
of a mountainous valley in Westmorland, called Grisedale, were marked in
many places with innumerable, almost horizontal, little ledges...Their
formation was in no way connected with the action of worms (and their
absence is an inexplicable fact)...(ibid., page 282.), mentioned in my
book and observed whilst I was correcting the proof-sheets, made me feel
rather doubtful. Yet the Corniche case (782/5. Ibid., page 281.) shows
that worms at least aid in making the ledges. Nevertheless, I wish I
had said nothing about the confounded ledges. The success of this worm
book has been almost laughable. I have, however, been plagued with an
endless stream of letters on the subject; most of them very foolish and
enthusiastic, but some containing good facts, which I have used in
correcting yesterday the "sixth Thousand."

Your friend George's work about the viscous state of the earth and tides
and the moon has lately been attracting much attention (782/6.
Published in the "Philosophical Transactions of the Royal Society,"
1879, 1880, 1881.), and all the great judges think highly of the work.
He intends to try for the Plumian Professorship of Mathematics and
Natural Philosophy at Cambridge, which is a good and honourable post of
about 800 pounds a year. I think that he will get it (782/7. He was
elected Plumian Professor of Astronomy and Experimental Philosophy in
1883.) when Challis is dead, and he is very near his end. He has all
the great men--Sir W. Thomson, Adams, Stokes, etc.--on his side. He has
lately been chief examiner for the Mathematical Tripos, which was
tremendous work; and the day before yesterday he started for Southampton
for a five-weeks' tour to Jamaica for complete rest, to see the Blue
Mountains, and escape the rigour of the early spring. I believe that
George will some day be a great scientific swell. The War Office has
just offered Leonard a post in the Government Survey at Southampton, and
very civilly told him to go down and inspect the place, and accept or
not as he liked. So he went down, but has decided that it would not be
worth his while to accept, as it would entail his giving up his
expedition (on which he had been ordered) to Queensland, in Australia,
to observe the Transit of Venus. (782/8. Major Leonard Darwin, late
R.E., served in several scientific expeditions, including the Transits
of Venus of 1874 and 1882.) Dear old William at Southampton has not
been very well, but is now better. He has had too much work--a willing
horse is always overworked--and all the arrangements for receiving the
British Association there this summer have been thrown on his shoulders.

But, good Heavens! what a deal I have written about my sons. I have had
some hard work this autumn with the microscope; but this is over, and I
have only to write out the papers for the Linnean Society. (782/9. i.
"The Action of Carbonate of Ammonia on the Roots of Certain plants."
[Read March 16th, 1882.] "Journ. Linn. Soc." Volume XIX., 1882, page
239. ii. "The Action of Carbonate of Ammonia on Chlorophyll-bodies."
[Read March 6th, 1882.] Ibid., page 262.) We have had a good many
visitors; but none who would have interested you, except perhaps Mrs.
Ritchie, the daughter of Thackeray, who is a most amusing and pleasant
person. I have not seen Huxley for some time, but my wife heard this
morning from Mrs. Huxley, who wrote from her bed, with a bad account of
herself and several of her children; but none, I hope, are at all
dangerously ill. Farewell, my kind, good friend.

Many thanks about the picture, which if I survive you, and this I do not
expect, shall be hung in my study as a perpetual memento of you.

(782/10. The concluding chapter of the "Life and Letters" gives some
account of the gradual failure in health which was perceptible in the
last year of Mr. Darwin's life. He died on April 19th, 1882, in his
74th year.)



[The German a-, o-, u-diaeresis are treated as a, o, u, not as ae, oe,

Aberrant genera, Darwin's work on.

Abich, on Vesuvius.

Abinger, excavations of Roman villa at.
-plants from.

Abinger Hall, Darwin visits.
-Lord Farrer's recollections of Darwin at.

Abiogenesis, Huxley's address on Biogenesis and.

Abortion, Romanes on.

Abrolhos, plants from the.


Abrus precatorius, dispersal of seeds.

Abstract, Darwin's dislike of writing papers in.

Abstract, the name applied by Darwin to the "Origin."

Abutilon, F. Muller's experiments on.

Abyssinia, flora of.

"Academy," Darwin's opinion of the.


Acceleration of development, Cope and Hyatt on retardation and.
-reference in the "Origin" to.

Accumulation, of deposits in relation to earth-movements.
-of specific differences.
-of sterility.
-of varieties.

Accuracy, difficult to attain.
-the soul of Natural History.

Aceras, fertilisation of.
-monstrous flower.

Acineta, Darwin unable to fertilise.

Aconitum, peloria and reversion.

Acropera, atrophy of ovules.
-Darwin's mistake over.
-fertilisation of.
-relation to Gongora.
-J. Scott's work on.

Acropera Loddigesii, abnormal structure of ovary.
-Darwin's account of flower.
-artificial fertilisation.
-relation to A. luteola.
-J. Scott's observations.
-two sexual conditions of.
-A. luteola, Darwin's observations on.
-fertilisation of.
-flowers of.
-structure of ovary.

Adaptation, Darwin's difficulty in understanding.
-hybrids and.
-not the governing law in Geographical Distribution.
-more clearly seen in animals than plants.
-Natural Selection and.
-in orchids.
-resemblances due to.
-in Woodpecker.

Adenanthera pavonina, seed-dispersal by Parrots.

Adenocarpus, a Mediterranean genus in the Cameroons.


Adoxa, difference in flowers of same plant.

Aecidium elatinum, Witches'-Broom fungus.

Aegialitis Sanctae-helenae.

Aegilops triticoides, hybrids.

Affaiblissement, A. St. Hilaire on.

Africa, connection with Ceylon.
-connection with India.
-continent of Lemuria and.
-considered by Murchison oldest continent.
-plants of equatorial mountains of.

Africa (East,) coral reefs on coast.

Africa (South), plants of.
-relation of floras of Western Europe to.

Africa (West), botanical relation to Java.

Agassiz, Alex., "Three Cruises of the 'Blake.'"
-his belief in evolution the result of F. Muller's writings.
-account of Florida Coral-reefs.
-letters to.
-visits Down.

Agassiz, Louis Jean Rodolphe (1807-73): entered a college at Bienne at the
age of ten, and from 1822 to 1824 he was a student at the Academy of
Lausanne. Agassiz afterwards spent some years as a student in the
Universities of Zurich, Heidelberg, and Munich, where he gained a
reputation as a skilled fencer. It was at Heidelberg that his studies took
a definite turn towards Natural History. He took a Ph.D. degree at
Erlangen in 1829. Agassiz published his first paper in "Isis" in 1828, and
for many years devoted himself chiefly to Ichthyology. During a visit to
Paris he became acquainted with Cuvier and Alexander von Humboldt; in 1833,
through the liberality of the latter, he began the publication of his
"Recherches sur les Poissons Fossiles," and in 1840 he completed his
"Etudes sur les Glaciers." In 1846 Agassiz went to Boston, where he
lectured in the Lowell Institute, and in the following year became
Professor of Geology and Zoology at Cambridge. During the last
twenty-seven years of his life Agassiz lived in America, and exerted a
great influence on the study of Natural History in the United States. In
1836 he received the Wollaston Medal of the Geological Society of London,
and in 1861 he was selected for the Copley Medal of the Royal Society. In
1873 Agassiz dictated an article to Mrs. Agassiz on "Evolution and
Permanence of Type," in which he repeated his strong conviction against the
views embodied in the "Origin of Species." See "Life, Letters, and Works
of Louis Agassiz," by Jules Marcou, 2 volumes, New York, 1896; "Louis
Agassiz: his Life and Correspondence," edited by Elizabeth Cary Agassiz, 2
volumes, London, 1885; "Smithsonian Report," 1873, page 198.
-attack on "Origin."
-Darwin's criticism of book on Brazil.
-Darwin's opinion of.
-views on creation of species.
-on geographical distribution.
-"Methods of Study" by.
-misstatement of Darwin's views.
-Walsh on.
-"Etudes sur les Glaciers."
-Darwin on glacier work of.
-on glaciers in Ceara Mts.
-glacier-ice-lake theory of Parallel Roads of Glen Roy.
-on glacier moraines.
-on rock-cavities formed by glacier-cascades.
-on Darwin's theory.
-on Geology of the Amazons.
-doubts recent upheaval of Patagonia.

Age of the world.

Aggressive plants, introduction of.

Agricultural Society, experiments on potatoes.

Airy, H. letter to.

Albemarle Island, Darwin's collection of plants from.
-volcanoes of.


Alerse ("Alerce"), occurrence in Chiloe.

Algae, movement of male-cells to female organ.

Alisma, F. Muller's observations on.
-submerged flowers of.

Alisma macrophylla, circumnutation of.

Allbutt, Prof. Clifford, on sperm-cells.

Allen, Grant, review by Romanes of his "Physiological Aesthetics."

Allen, J.A., on colours of birds.
-on mammals and birds of Florida.

Allogamy, use of term.

Almond, seedling peaches resembling.

Alopecurus pratensis, fertilisation of.

Alpine floras, Arctic and.
-of Azores, Canaries and Madeira.
-absence of, in southern islands.
-Ball on origin of flora.
-Darwin's work on.
-of United States.
-existence prior to Glacial period.
-Ice-action in New Zealand, and.
-Ball on origin of.

Alpine insects.

Alpine plants.
-change due to transplanting.
-slight change in isolated forms.
-as evidence of continental land at close of Glacial period.

Alps, Australian.
-Murchison on structure of.
-Tyndall's book on.

Alternate generations, in Hydrozoa.

Amazonia, Insects of.

Amazons, L. Agassiz on glacial phenomena in valley of.
-L. Agassiz on geology of.
-Bates on lepidoptera of.
-sedimentation off mouth of.

Amber, extinct plants preserved in.

Amblyopsis, a blind cave-fish, effect of conditions on.

Ameghino, Prof., discovery of Neomylodon Listai.

America (North), are European birds blown to?
-Falconer on elephants.
-fauna and flora of Japan and.
-flora of.
-mammalian fauna.
-introduction of European weeds.
-subsidence during Glacial period.
-western European plants and flora of.
-contrast during Tertiary period between South and.
-former greater distinction between fauna of South and.
-glaciation of South and.
-Rogers on coal-fields.

America (South), Bollaert's "Antiquities" of.
-Araucarian fossil wood from.
-Carabi of.
-elevation of coast.
-fauna of.
-floras of Australia and.
-geology of.
-Darwin's "Geological Observations" on.
-deposition of sediment on coast.
-European plants in.
-frequency of earthquakes.
-D. Forbes on geology of.
-W. Jameson on geology of.
-D'Orbigny on.
-volcanic eruptions.
-Wallace opposed to continent uniting New Zealand, Australia and.

American War.

Ammonia, Darwin's work on effect on roots of carbonate of.

Ammonites, degeneration of.
-of S. America.


Amsinckia spectabilis, dimorphism of.

Anacamptis (=Orchis pyramidalis), fertilisation of.

Anacharis (=Elodea Canadensis), spread of.

Analogy, difference between homology and.

Anamorphism, Huxley on.

Anatifera, illustrating difficulty in nomenclature.

Anatomy of Vertebrata, Owen's attack on Darwin and Lyell in.

"Ancient Sea Margins," by R. Chambers.

Anderson-Henry, Isaac (1799?-1884): of Edinburgh, was educated as a
lawyer, but devoted himself to horticulture, more particularly to
experimental work on grafting and hybridisation. As President of the
Botanical Society of Edinburgh he delivered two addresses on
"Hybridisation or Crossing of Plants," of which a full abstract was
published in the "Gardeners' Chronicle," April 13th, 1867, page 379, and
December 21st, 1867, page 1296. See obit. notice in "Gardeners'
Chronicle," September 27th, 1884, page 400.
-letter to.

Andes, Darwin on geology of.
-high-road for European plants.
-comparatively recent origin.

Anemophilous plants, Delpino's work on.

Angiosperms, origin of.

Angraecum sesquipedale, Duke of Argyll on.

Animal Intelligence, Romanes on.

Animals, difference between plants and.
-resemblance to plants.

Annuals, adapted to short seasons.
-Hildebrand on percentages of.

Anoplotherium, occurrence in Eocene of S. America.

Ansted, David Thomas, F.R.S. (1814-80): Fellow of Jesus College, Cambridge,
Professor of Geology at King's College, London, author of several papers
and books on geological subjects (see "Quart. Journ. Geol. Soc." Volume
XXXVII., page 43.)
-letter to.

Antarctic continent, Darwin on existence of Tertiary.

"Antarctic Flora," Sir J.D. Hooker's.

Antarctic floras.
-Darwin at work on.

Antarctic islands, plants of.

Antarctic Land.

"Anti-Jacobin," quiz on Erasmus Darwin in.

"Antiquity of Man," Sir Charles Lyell's.
-cautious views on species.
-Darwin's criticism of.
-Extract on Natural Selection from.
-Falconer on.
-Owen's criticism on.

Antirrhinum, peloric flowers.

Ants, account in "Origin" of Slave-.
-Forel's work on.
-Moggridge on Harvesting-.
-F. Muller's observations on neuter.
-storing leaves for plant-culture.

Apathus, living in nests of Bombus.

Apes, comparison as regards advance in intellect between man and.
-ears of anthropoid.

Aphides, absence of wings in viviparous.

Aphis, Huxley on.

Apostasia, morphology of flowers.

Appalachian chain, Rogers on cleavage of.

Apteryx, Owen on.
-wings of.

Aquilegia, Hooker and Thomson on.
-variation in.
-peloria and reversion.

Arachis hypogaea, Darwin on.


Araucaria, abundant in Secondary period.

Araucarian wood, fossil in S. America.

Arca, Morse on.


Archer-Hind, R.D., translation of passage from Plato by.

Archetype, Owen's book on.
-Owen's term.

d'Archiac's "Histoire des Progres de la Geologie."
-candidate for Royal Society Foreign list.

Arctic animals, protective colours.

Arctic climate, cause of present.

Arctic expeditions, Darwin on.

Arctic floras.
-relation between Alpine and.
-relation between Antarctic and.
-Hooker's Essay on.
-Darwin's admiration of Hooker's Essay.
-migration of.

Arctic regions, few plants common to Europe and N. America not ranging
-range of plants.
-northern limit of vegetation formerly lower.
-ice piled up in.
-previous existence of plants in.

Arenaria verna, range.

Argus pheasant, colour.
-unadorned head.

Argyll, Duke of, attack on Romanes in "Nature."
-rejoinder by Romanes in "Nature."
-Hooker on.
-letter to.
-"Reign of Law" by.

Aristolochia, fertilisation of.

Aristotle, reference to.

Ark, Fitz-Roy on extinction of Mastodon owing to construction of.


Army, measurement of soldiers of U.S.A.

Artemia, Schmankewitsch's experiments on.

Ascension Island, plants of.
-volcanic rocks.

Ascidians, budding of.

Asclepiadeae, fertilisation of.

Ash, comparison of peat and coal.

Asher, Dr., sends Russian wheat to Darwin.


Ashley Heath, Mackintosh on boulders of.

Askenasy, E., on Darwinism.


Ass, hybrids between mare and.


Astragalus hypoglottis, range of.

Astronomical causes, crust-movements due to.

Asturian plants in Ireland.

Atavism, use of term by Duchesne.
-Kollmann on.

Athenaeum Club, Huxley's election.

"Athenaeum," correspondence on Darwin's statements on rate of increase
of elephants.
-Darwin's opinion of.
-abuse of Darwin.

Atlantic islands, peculiar genera and their origin.

Atlantis, America and.
-Canary I. and.
-Darwin's disbelief in.
-Heer's map.

Atolls, Darwin's wish for investigation by boring of coral.
-Darwin on Murray's theory.
-Darwin's work on.

Atomogenesis, term suggested as substitute for pangenesis.

Atriplex, buried seeds found in sandpit near Melrose.

Attica, Gaudry on fossil animals.

Auckland Island, flora.

Audubon, J.J., on antics of birds during courtship.
-"Ornithological Biography."

Aurelia, Romanes on.

Auricula, dimorphism of.
-experiments on.

Austen, Godwin, on changes of level on English coast.

Australia, caves of.
-character of fauna.
-flora of.
-Hooker on flora.
-relation of flora to S. America.
-relation of flora to S. Africa.
-European plants in.
-local plants in S.W.
-naturalised plants.
-plants on mountains.
-fossil plants.
-dichogamy of trees in.
-as illustrating rate and progress of evolution.
-Mastodon from.
-products of, compared with those of Asia.

Australian savages and Natural Selection.

Australian species, occurrence in Malay Archipelago and Philippines.

Autobiographical recollections, Charles Darwin's.

Autobiography, extract from Darwin's.

Autogamy, Kerner's term.

Automatism, Huxley's Essay.

Avebury, Lord.
-address at British Association meeting at York (1881).
-on the Finns and Kjokken moddings.
-letters to.
-on the "Origin."
-"Prehistoric Times."
-on the Progress of Science.
-on Seedlings.
-story of Darwin told by.
-Darwin regrets his entrance into politics.
-on Ramsay's lake-theory.

Averrhoa, Darwin's work on.

Axell, Severin, book on fertilisation of plants.

Axon, W.E., letter from Darwin to Mrs. E. Talbot published by.

Aye Aye, Owen on the.


Azores, organic relation with America.
-European birds as chance wanderers to.
-erratic blocks.
-European plants in.
-Miocene beds in.
-relation to Madeira and Canaries.
-Watson on the.
-Orchids from.

Babies, habit of clutching objects.

Babington, Prof. Charles C., at the British Association (Manchester,
-"British Flora."
-Darwin sends seeds of Atriplex to.

Baden-Powell, Prof.


Bagehot, W., article in "Fortnightly Review" on Physics and Politics.

Bahia Blanca, collection of plants from.

Bailey, on Heterocentron roseum.

Baillon, on pollen-tubes of Helianthemum.

Baker's Flora of the Mauritius and Seychelles.

Balancement, G. St. Hilaire's law of.

Balanidae, Darwin's work on.

Balanus, questions of nomenclature.

Balfour, F.M. (1851-82): Professor of Animal Morphology at Cambridge.
He was born 1851, and was killed, with his guide, on the Aiguille
Blanche, near Courmayeur, in July 1882. (See "Life and Letters," III.,
page 250.)
-letter to.

Ball, J., on origin of Alpine flora.

Ball, P., "The effects of Use and Disuse."

Balsaminaceae, genera of.

Banks' Cove, volcano of.

Barber, C., on graft-hybrids of sugar-cane.

Barber, Mrs., on Papilio nireus.

Barberry, abundance in N. America.
-dispersal of seeds by birds.
-Lord Farrer and H. Muller on floral mechanism.
-movement of stamens.

Barbs, see Pigeons.

Bardfield Oxlip (Primula elatior).

Barnacles, Darwin's work on.
-metamorphosis in.
-F. Muller on.
-of Secondary Period.
-advance in.
-complemental males compared with plants.

Barneoud, on irregular flowers.

"Baronne Prevost," Rivers on the rose.

Barrande, Joachim (died 1883): devoted himself to the investigation of
the Palaeozoic fossils of Bohemia, his adopted country. His greatest
work was the "Systeme Silurien de la Boheme," of which twenty-two
volumes were published before his death. He was awarded the Wollaston
Medal of the Geological Society in 1855. Barrande propounded the
doctrine of "colonies." He found that in the Silurian strata of
Bohemia, containing a normal succession of fossils, exceptional bands
occurred which yielded fossils characteristic of a higher zone. He
named these bands "colonies," and explained their occurrence by
supposing that the later fauna represented in these "precursory bands"
had already appeared in a neighbouring region, and that by some means
communication was opened at intervals between this region and that in
which the normal Silurian series was being deposited. This apparent
intercalation of younger among older zones has now been accounted for by
infoldings and faulting of the strata. See J.E. Marr, "On the Pre-
Devonian Rocks of Bohemia," "Quart. Journ. Geol. Soc." Volume XXXVI.,
page 591 (1880); also "Defense des Colonies," by J. Barrande (Prag,
1861), and Geikie's "Text-book of Geology" (1893), page 773.
-candidature for Royal medal.
-candidate for Royal Society foreign list.
-work on Colonies.
-Lyell on work of.

Barriers to plant distribution in America.

Barrow, on Emberiza longicauda.
-"Travels in S. Africa."

Barrow, Sir J., connection with naval expeditions.

Barrow, germination of seeds from a.

Bartlett, Abraham Dee (1812-97): was resident superintendent of the
Zoological Society's Gardens in Regent's Park from 1859 to 1897. He
communicated several papers to the Zoological Society. His knowledge was
always at the service of Mr. Darwin, who had a sincere respect for him.
-letters to.

Barton, on trees of N. America.

Basalt, association with granite.
-separation of trachyte and.

Basques, H. Christy on the.
-Hooker on Finns and.

Bastian, "The Beginnings of Life."

Bat, natural selection and increase in size of wings.

Bates, Henry Walter (1825-92): was born at Leicester, and after an
apprenticeship in a hosiery business he became a clerk in Allsopp's
brewery. He did not remain long in this uncongenial position, for in 1848
he embarked for Para with Mr. Wallace, whose acquaintance he had made at
Leicester some years previously. Mr. Wallace left Brazil after four years'
sojourn, and Bates remained for seven more years. He suffered much ill-
health and privation, but in spite of adverse circumstances he worked
unceasingly: witness the fact that his collection of insects numbered
14,000 specimens. He became Assistant Secretary to the Royal Geographical
Society in 1864, a post which he filled up to the time of his death in
1892. In Mr. Clodd's interesting memoir prefixed to his edition of the
"Naturalist on the Amazons," 1892, the editor pays a warm and well-weighed
tribute to Mr. Bates's honourable and lovable personal character. See also
"Life and Letters," II., page 380.
-"A Naturalist on the Amazons."
-Darwin's opinion of his work.
-on insect fauna of Amazon Valley.
-on lepidoptera of Amazons.
-letter from Hooker to.
-letters to.
-letter to Hooker from.
-Darwin reviews paper by.
-on flower of Monochaetum.
-on insects of Chili.
-supplies Darwin with facts for sexual selection.

Bateson, Miss A., on cross fertilisation in inconspicuous flowers.

Bateson, W., on breeding lepidoptera in confinement.
-Mendel's "Principles of Heredity."

Batrachians, Kollmann on rudimentary digits.

Bauer, F., drawings by.

Bauhinia, sleep-movements of leaves.

Beaches, S. American raised.

"Beagle" (H.M.S.), circumstance of Darwin joining.
-Darwin's views on species when on.
-FitzRoy and voyage of.
-return of.

Beans, holes bitten by bees in flowers.
-extra-floral nectaries of.

Bear, comparison with whale.
-modification of.

Beaton, Donald (1802-63): Biographical notices in the "Journal of
Horticulture" and the "Cottage Gardener," XIII., page 153, and "Journ.
Hort." 1863, pages 349 and 415, are referred to in Britten & Boulger's
"Biographical Index of Botanists," 1893. Dr. Masters tells us that
Beaton had a "first-rate reputation as a practical gardener, and was
esteemed for his shrewdness and humour."
-Darwin on work of.
-on Pelargonium.

Beatson, on land birds in S. Helena.


Beaufort, Captain, asks Darwin for information as to collecting.

Beaumont, Elie de (1798-1874): was a pupil in the Ecole Polytechnique
and afterwards in the Ecole des Mines. In 1820 he accompanied M.
Brochant de Villiers to England in order to study the principles of
geological mapping, and to report on the English mines and metallurgical
establishments. For several years M. de Beaumont was actively engaged
in the preparation of the geological map of France, which was begun in
1825, and in 1835 he succeeded M. B. de Villiers in the Chair of Geology
at the Ecole des Mines. In 1853 he was elected Perpetual Secretary of
the French Academy, and in 1861 he became Vice-President of the Conseil
General des Mines and a Grand Officer of the Legion of Honour. Elie de
Beaumont is best known among geologists as the author of the "Systemes
des Montagnes" and other publications, in which he put forward his
theories on the origin of mountain ranges and on kindred subjects.
("Quart. Journ. Geol. Soc." Volume XXXI.; "Proc." page xliii, 1875.)
-on lines of elevation.
-on elevation in Cordilleras.
-elevation-crater theory.
-Darwin's disbelief in views and work of.
-on lava and dykes.
-Lyell's refutation of his theory.
-measurement of natural inclination of lava-streams.

Beauty, criticism by J. Morley of Darwin's phraseology in regard to.
-discussion on.
-lepidoptera and display of.
-Wallace on.
-Darwin's discussion on origin.
-in female animals.
-in plumage of male and female birds.
-of seeds and fruits.
-Shaw on.
-standards of.

Bedford, flint implements found near.

Beech, in Chonos I.
-in T. del Fuego and Chili.
-Miquel on distribution.

Bee-Ophrys (Ophrys apifera), see Bee-Orchis.

Bee-Orchis, Darwin's experiments on crossing.
-intermediate forms between Ophrys arachnites and.

Bees, combs.
-Haughton on cells of.
-and instinct.
-referred to in "Descent of Man."
-New Zealand clover and.
-acquisition of power of building cells.
-Darwin's observations on.
-agents in fertilisation of papilionaceous flowers.
-as pollen collectors.
-difference between sexes.
-H. Muller on.
-and parthenogenesis.
-regular lines of flight at Down.

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