360 



COMPARATIVE ZOOLOGY 



FIG. 314. Skeleton of the Horse (Equus caballus): 22, premaxillary; 12, foramen in 

 the maxillary; 15, nasal; 9, orbit; 19, coronoid process of lower jaw; 17, surface of 

 implantation for the masseter muscle ; there are seven cervical vertebrae, nineteen 

 dorsal, D D; five lumbar, a-e ; five sacral,/^// and seventeen caudal, />-?/ 51, 

 scapula, or shoulder blade ; /, spine, or crest; //; coracoid process (acromion wanting) ; 

 i > first" pair of ribs (clavicle wanting, as in all Ungulates); e, sternum; a, shaft of 

 humerus; b, deltoid ridge; g head fitting in the glenoid cavity of the scapula near 

 it is a great tuberosity for the attachment of a powerful muscle; k, condyles; 54, 

 radius, to which is firmly anchylosed a rudimentary ulna, 55, the olecranon; 56, the 

 seven bones of the carpus, or wrist; 57, large metacarpal, or " cannon bone," with 

 two "splint bones"; 58, fetlock joint; 59, phalanges of the developed digit, corre- 

 sponding to the third finger in man; 62, pelvis; 63, the great trochanter, or prom- 

 inence on the femur, 65; 66, tibia; 67, rudimentary fibula; 68, hock, or heel, falsely 

 called knee; 69, metatarsals. 



