My dear M^r Blyth

Many thanks for your last M.S. I am very glad to hear about the colours of Hylobates.² Unfortunately, I cannot find in Isidor Geoffroy Hist. des Anom. any statement in regard to which digits in man are most liable to syndactylism; if I c^d ascertain this point your remark w^d be most interesting.³ I knew about the variability of the junction of the digits in some of the species.

I have been reading over the M.S. which you sent me some weeks ago, with much interest.

Do I read correctly that the black colour in certain terns is a seasonal change either in the males or both sexes?⁴

I sh^d be particularly obliged if you w^d tell me whether the Gallicrex cristatus, during the breeding season, becomes ornamented in any way to an unusual degree in comparison with other members of the same family: I want to know because you say that it is probably polygamous.⁵

Forgive me for asking two other questions. Do you know whether the plumes are more developed in the male ostritch than in the female?

2^ndly Do you chance to know whether the male woodpecker takes a share in incubation?

With many thanks for yr never failing kindness in assisting me, believe me | yours very sincerely | Ch. Darwin