Hyperythra, proportion of the sexes in.
Hypogymna dispar, sexual difference of colour in.
Hypopyra, coloration of.
Ibex, male, falling on his horns; beard of the.
Ibis, white, change of colour of naked skin in, during the breeding
season; scarlet, young of the.
Ibis tantalus, age of mature plumage in; breeding in immature plumage.
Ibises, decomposed feathers in; white; and black.
Ichneumonidae, difference of the sexes in.
Ichthyopterygia.
Ichthyosaurians.
Idiots, microcephalous, their characters and habits; hairiness and
animal nature of their actions; microcephalous, imitative faculties of.
Iguana tuberculata.
Iguanas.
Illegitimate and legitimate children, proportion of the sexes in.
Imagination, existence of, in animals.
Imitation, of man by monkeys; tendency to, in monkeys, microcephalous
idiots and savages; influence of.
Immature plumage of birds.
Implacentata.
Implements, employed by monkeys; fashioning of, peculiar to man.
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