114 COMPARATIVE OSTEOLOGY. 



"hallux of man, is very generally only a ligamentous cord, ULWliicli is found a 

 short bone, which represents a phalanx. 



Fig. 33. Fio. 84. 



Clavicle of a Dog— enlarged one-half. Clavicle of a Cat— natural size. 



VISCERAL SKELETON. 



In carnivora, generally speaking, there is & davicle^ but it is incomplete, and 

 is found embedded in the soft structures between the sternum and shoulder. 

 In the dog it is often represented by a piece of ligamentous tissue, and when 

 it does exist as a bone, it is very small and somewhat triangular in shape. | 



The Felidse or cat tribe possess a clavicle which, to a certain extent, 

 j:esembles in shape that of the human subject, being elongated, rounded, and 

 slightly curved. Occasionally this bone in the cat is continued by ligaments, 

 which unite it both to the sternum and to the acromion process. 



Os Penis. 



This is a single bone very generally found in the penis of the carnivora, and 

 alVvays in the dog ; in the cat it is said to be less persistent, and when present 

 much smaller. It is a thin piece of bone hollowed to form a longitudinal 



Fig. 35. 

 Os Penis of a Dog, half the size of that of a large animal. 

 a a. Inferior groove ; 6, Anterior end . c, Posterior end. 



groove, in which the uretha lies; the groove ceases anteriorly, and at' this 

 extremity the bone becomes flat and pointed. Both extremities are prolonged 

 by cartilages. 



RODENTIA. 



This large order we have already mentioned as bfeing characterised by its 

 peculiar dentition. One representative of the order is the common Rabbit,' 

 which belongs to the family Leporidse. 



Axial Skeleton. 



There are 12 dorsal, 7 lumbar, and 4 sacral vertebrae. The wing of the 

 <itlas presents no foramina externally, but there is a very large notch in its 

 anterior border, inside which is the cerebro-spinal foramen. As in the 

 carnivora, there is no atlo-axoid space. The centra of the cervical vertebras 

 are short, broad, and strong ; while those of the dorsal region gradually 

 increase in length backwai'ds. ■ The lumbar vertebra are largely developed,^ 



