much staggered about the permanence o£ species. I must say one 
word more in justification (for I feel sure that your tendency 
will be to dispare over my contents) that all my notions about ^ 
how species change are derived from long continued study of the 
works of (and concern with) agriculturalists and horticul turalis ts ; 
and I believe I see my way pretty clearly on the means used by 
nature to change the species and adapt them to the conditions and 
exquisitely beautiful contingencies to which every living being 
is exposed. 
I thank you much for what you say about variability and cross- 
ing of the grasses: I have been often astounded at what Botanists 
say on fertijlizat ion in the bud: I have seen Cincifera mentioned 
as instances, which every gardener knows how difficult it is to 
protect from cupingl What you say on Popilionaceous flowers is 
very true; and I have no facts to show the varieties are cuped; 
but yet (and the same remark is applicable in a beautiful way to 
Frumaria and Dielytia as I noticed many years ago) I must believe 
that the flowers are constructed partly in direct relation to 
insects' visits; and how insects can avoid bringing pollen from 
other individuals I cannot understand. It is really pretty to 
watch the action of a Humble-Bee on the scarlet Kidney Bean, and 
in this genus (and in Lathrus Grand, flowers) the honey is so 
placed that the Bee invariably alights cn the side of the flower 
towards which the pistol is pointed (bringing out with it pollen) 
and by the depression of the wing-petal is forced against the 
Bees' side all dusted with pollen. In the Broom the pistol is 
rubbed on centre of back of Bee. I suspect there is something to 
be made out about the Leguminosae which will bring the case within 
our theory: though I have failed to do so. For theory will ex- ^ 
plain why in vegetable and animal Kingdoms the act of fertilization 
even in hermaphrodites usually takes place sub-jove, though thus 
exposed to the great injury from damp and rain. In animals in 
which the semen cannot, like pollen be occasionally carried by 
insects or wind: there is no c ase of Land -animals being hermaph- 
rodite without the concourse of two individuals. But my letter 
has been horribly egotistical : but your letters always so greatly 
interest me; and what is more they have in simple truth, been of 
the utmost value to me. 
Yours most sincerely and gratefully 
C. Darwin 
Gray Papers, Harvard University. Published in Nathan Reingold, ^ 
e d . , Science in Ni n e teenth- Century America (New - York, 1964), 18 7-189 
