Nasals long in early, but shorter in later forms, hornless; orbit open behind.
Hornless rhinoceroses, with five fronttoes, ranging from the Oligocene to the Lower Pliocene in Europe, represent the genus Aceratherium, which may also occur in America, as it certainly does in India.
Picticaudata form a group in which the females are hornless and the face-markings inconspicuous or wanting.
The Theban goat, of the Sudan, which is hornless, displays the characteristic features of the last in an exaggerated degree, and in the form of the head and skull is very sheep-like.
From this it seems probable that Palaeotragus and Ocapia indicate the ancestral type of the giraffe-line; while it has been further suggested that the apparently hornless Helladotherium of the Female Okapi.
Helladotherium was a much larger animal, known by a single hornless skull from the Pliocene of Greece, which may be that of a female.
Galloway also gives its name to a famous indigenous breed of black hornless cattle.
This belief seems to be especially prevalent amongst breeders of cattle; but how, for example, a long-horned Highland bull, used for crossing with black hornless Galloway cows, could subsequently get Galloway-like calves out of pure Highland heifers it is impossible to imagine.
Although many of the domesticated breeds are hornless, sheep belong to the family of hollow-horned ruminants or Bovidae.
The ewes are hornless, but in Africa the rams have very short, thick and somewhat goatlike horns.
The Ryeland sheep are small, hornless, have white faces and legs, and remarkably fine short wool, with a topknot on the forehead.
The Dartmoor, a hardy local Devonshire breed, is a large hornless, longwool, white-fleeced sheep, with a long mottled face.
Polled, or hornless, breeds, such as the polled Angus and polled Suffolk, are of interest, as showing how easily the horns can be eliminated, and thus indicating a hornless ancestry.