Hookham, Mr., on mental concepts in animals.
Hoolock Gibbon, nose of.
Hoopoe, sounds produced by male.
Hoplopterus armatus, wing-spurs of.
Hornbill, African, inflation of the neck-wattle of the male during courtship.
Hornbills, sexual difference in the colour of the eyes in; nidification and incubation of.
Horne, C., on the rejection of a brightly-coloured locust by lizards and birds.
Horns, sexual differences of, in sheep and goats; loss of, in female merino sheep; development of, in deer; development in antelopes; from the head and thorax, in male beetles; of deer; originally a masculine character in sheep; and canine teeth, inverse development of.
Horse, fossil, extinction of the, in South America; polygamous; canine teeth of male; winter change of colour.
Horses, rapid increase of, in South America; diminution of canine teeth in; dreaming; of the Falkland Islands and Pampas; numerical proportion of the sexes, in; lighter in winter in Siberia; sexual preferences in; pairing preferently with those of the same colour; numerical proportion of male and female births in; formerly striped.