lO 



MAMMALS 



region, this being true of both the giraffe and the whale. 

 In the former each bone is lengthened out, while in the 

 whale it is so very short that this huge creature, the larg- 

 est of all animals, can hardly be said to have a neck at all. 

 In the back there are usually thirteen bones, sometimes 

 more. In the tail the bony links, or vertebrae, number 

 from four to forty-five. The head is large and solid, form- 



FiG. I. — Skeleton of a Wild Ass. 



i, incisor teeth; g, grinding teeth, with the gap between the two sets as in all large 

 grass feeders; k, knee; h, heel; /, foot; /, middle toe of three joints carrying 

 the hoof; s, splint, or remains of one of the two lost toes; e, elbow; w, wrist; 

 ha, hand bone ; i, 2, 3, joints of the middle toe. 



ing a perfect and heavy covering for the brain. It moves 

 easily from side to side, or up and down, permitting the 

 animal to see in almost any direction. The lower jaw is 

 composed of two pieces. It is joined directly to the skull, 

 and not to a quadrate bone, as in the birds. The vertebrae 

 of the back support the ribs, which curve downward and 



