it. The old doctrine of immutability of specific forms will surely but
slowly die away. It is a shame to give you trouble, but I should be very
much obliged if you could tell me where differently coloured eggs in
individuals of the cuckoo have been described, and their laying in twenty-
seven kinds of nests. Also do you know from your own observation that the
limbs of sheep imported into the West Indies change colour? I have had
detailed information about the loss of wool; but my accounts made the
change slower than you describe.

With most cordial thanks and respect, believe me, my dear Carpenter, yours
very sincerely,
CH. DARWIN.


CHARLES DARWIN TO L. JENYNS. (Rev. L. Blomefield.)
Down, January 7th, 1860.

My dear Jenyns,

I am very much obliged for your letter. It is of great use and interest to
me to know what impression my book produces on philosophical and instructed
minds. I thank you for the kind things which you say; and you go with me
much further than I expected. You will think it presumptuous, but I am
convinced, IF CIRCUMSTANCES LEAD YOU TO KEEP THE SUBJECT IN MIND, that you
will go further. No one has yet cast doubts on my explanation of the
subordination of group to group, on homologies, embryology, and rudimentary
organs; and if my explanation of these classes of facts be at all right,
whole classes of organic beings must be included in one line of descent.

The imperfection of the Geological Record is one of the greatest