a bison, but among the ungulates we have passed over, there are certain
others which concern us because they are American.

Sheep and goats agree together and differ from oxen in being usually of
smaller size; the tail is shorter, the horns of females are much smaller
than those of males, they lack the accessory column on the inner side of
the upper molars, and the cannon bone is longer and more slender; but
when it comes to a comparison of the one with the other, it is by no
means always easy to tell the difference. It is true that the early
Greeks seem to have had a rough and ready rule under which mistakes were
not easy, for Aristotle tells us "Alcmaeon is mistaken when he says that
goats breathe through their ears," but the severely practical methods of
our own day leave us little but some very minute points of
difference. One of the best of these lies in the shape of the
basi-occipital bone, but naturally this can be observed only in the
prepared skull. The terms often employed to denote difference in the
horns can have only a general application, for they break down in
certain species in which the two groups approach each other. The
following table expresses some fairly definite points of separation:


SHEEP (_Ovis_). GOAT (_Capra_).

1. Muzzle hairy except between 1. Muzzle entirely hairy.
and just above the
nostrils.

2. Interdigital glands on all 2. Interdigital glands, when
the feet. present, only on fore feet.