Returns MS [of "Variation of species"]; several facts were new to him, especially interested in wagtails.
Wishes he could swallow Florent Prévost on sparrows ["Du régime alimentaire des oiseaux", C. R. Hebd. Acad. Sci. 46 (1858): 136–8].
LJ’s facts seem to bear out CD’s conclusion that secondary sexual characters were most variable of all.
Explains how he intends to deal with variation, and general facts in natural history in the light of species theory. Can only afford one chapter on variation in nature. It seems more important to make out variation in domestic animals.
Asks for facts on birds’ nests for his chapter on instincts.