XXI 
HORNS 
267 
Europe, need not detain us long, for deer are not found 
in Africa. Structurally, they are outgrowths from the 
frontal bone, and consist entirely of bone. During their 
t^rowth, antlers are covered with skin beset with hairs 
and sebaceous glands ; the skin covering an antler is 
continuous with that on the deer’s head; so long as its 
antlers are covered with skin, the stag is said to be “ in 
velvet.” 
Antlers in this condition are sensitive to knocks and 
blows, but when full-grown the velvet peels off and the 
bare bone remains. Peeled antlers are insensitive, and 
the bucks use them to fight rivals. In fighting, the 
antlers are used with such violence that a tine or 
occasionally the beam is broken. At the end of the 
rutting season the antlers fall off, and are annually 
renewed. In the majority of deer it is the buck alone 
which is ornamented with horns. 
The rapidity with which antlers grow is astonishing. 
The Wapiti {Cervus canadensis) has antlers weighing 
thirty-two or more pounds, yet these huge masses of 
bone are reproduced in five months. In the Zoological 
Gardens during the growth of the antlers it is usual to 
double the wapiti’s allowance of food. 
Horns of the second kind are characteristic of the 
Family Bovidce, which comprises oxen, sheep, goats, 
and antelopes. These animals are sometimes called the 
sheath-horned ruminants, because their horns consist of 
a core of bone connected with the frontal bone, covered 
with a sheath of hard material derived from the super¬ 
ficial (epithelial) layer of the skin. This horny sheath 
corresponds to the velvet of the deer’s antler, but it is 
insensitive. Mammals possessing such horns are some¬ 
times spoken of as the Cavicornia or Hollow-horned. 
These horns differ from antlers in the fact that they 
are never shed and never branch. 
The horns of antelopes present great variety in shape 
and size. They are also useful to the zoologist for the 
purposes of classification. 
