THE MAMMALS 237 



thirty to over a hundred feet in length with a weight of 

 many tons. 



222. Hoofed mammals (Ungulata). The order of hoofed 

 animals or ungulates includes a large number of forms like 

 the zebra, elephant, hippopotamus, giraffe, deer, and several 

 other wild species, some of which are domesticated, such 

 as horses, sheep, goats, and cattle. All of these animals 

 walk on the tips of their toes, and the claws have become 

 developed into hoofs. The order is divided into the odd- 

 toed forms (perissodactyls), such as the rhinoceros with 

 three toes and the horse with one, and the even-toed (artio- 

 dactyls), as the pigs with four, and the ox, deer, etc., with 

 two toes. . The even-toed forms are again divided into 

 those which chew the cud (ruminants) and those which do 

 not (non-ruminants). Xo living native odd-toed mammal 

 exists in this country, and of the wild even-toed species all 

 are ruminants. In the members of this latter group the 

 swallowed food passes into a capacious sac (the paunch), is 

 thoroughly moistened, and passed into the second division 

 (the honeycomb), later to be regurgitated and ground by 

 the powerful molars. It is then reswallowed, and under- 

 goes successive treatment in the other two divisions of 

 the stomach (the manyplies and reed) before entering the 

 intestine. 



Among the North American ruminants, the deer fam- 

 ily ( Cervidce) is the best represented. In the more unsettled 

 regions of the East the red deer is still common, and the 

 same may be said of the white-tailed, black-tailed, and 

 mule-deer of the West. Among the woods and lakes to 

 the northward live the reindeer and caribou, and the largest 

 of the deer family, the moose, which attains the size of the 

 horse. Of nearly the same size is the wapiti or elk, whose 

 general characters are shown in Fig. 134. In all of the 

 above-mentioned species the horns, if present, are confined 

 to the male (except in the reindeer), and are annually shed 

 after the breeding season. 



