Discusses apes and their relationships to each other. Writes particularly of the gibbon, its structure and well-developed legs giving it the ability to walk without using its hands.

Glad to hear about colours of Hylobates.

Cannot find any statement about which digits in man are most subject to syndactylism in Isidore Geoffroy [Saint-Hilaire]’s Histoire des anomalies [1832–7].

Asks questions concerned with seasonal and sexual changes in plumage of various bird species.

Does male woodpecker share in incubation?

Discusses the human foot and its abnormalities; notes an example of syndactylism.

Gives his observations on sexual differences in coloration of terns and ostriches.