Aggressive behaviour of a bullfinch toward new arrival in JJW’s aviary.

Sexual differences in goldfinches: size of beaks.

Sexual selection in Lepidoptera.

Thinks Dr Alex Wallace’s observations on Bombyx not conclusive in proving that no preference is shown by females.

Does not think females give preference to any males. Coloration, pugnacity; cases of use of colour in struggle for existence. [see Descent 1: 395.]

Various facts about birds: pairing, finding new mates, protective coloration, polygamy, sexual differences.

Courtship of goldfinches. Male display. [See Descent 2: 95.]

Sexual selection of pigeons, ducks;

polygamous birds.

Relates a variety of facts about sexual selection in birds. [See Descent 2: 104–5.]

Experiments to test Wallace’s theory that brightly coloured caterpillars are rejected by birds. [See Descent 1: 417.]

Proportions of sexes in birds as reported by bird-catchers.

Sexual behaviour of chaffinches.

Numbers of female linnets in September.

His experiments on brightly coloured larvae [as food], testing A. R. Wallace’s theory.

His observations of a rookery make him wonder whether it may not be more difficult than we think for birds to pair.