THE SKIN AND SKELETON. 



151 



Pig. 117.— Skeleton of the Horse (Equus caballus) : 22, prcmaxillary ; 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, nine- 

 teen dorsal, D-D; five lumbar, a-e; five sacral, f-l; and seventeen caudal, p-r; 

 51, scapula, or shoulder-blade ; i, spine, or crest ; ft, coracoid process (acromion 

 wanting) ; 1, first pair of ribs (clavicle wanting, as in all Ungulates) • e, sternum : 

 a, shaft of humerus; 6, 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 y 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, corresponding to the third finger in Man ; 62, pelvis ; 63, the 

 great trochanter, or prominence on the femur, 65 ; 66, tibia ; 67, rudimentary 

 fibula ; 68, hock, or heel, falsely called knee ; 69, metatarsals. 



