LEPUS. 



397 



The sacral vertebrce are two. They are ankylosed 

 together and are firmly joined to the ilium. 



The caudal vertebrce vary in number up to twenty. The 

 first few are ankylosed to the sacral vertebrae; the rest 

 gradually become simpler till they are mere rods of bone 

 representing the centra only. 



Compared with that of the pigeon, the vertebral column 

 of the rabbit exhibits far less adaptive modification, espe- 

 cially in the direction of fusions. With the exception of 



Fig. 288. — Pectoral Girdle and Fore-limb of the 

 Rabbit. {Ad nat.) 



^ . , -r. -^ Supratrochlear Foramen, 



Coracoid Process. ^ — 



A, Scapula. B, Humerus. C, Radius and Ulna. 



the first few caudals, there is no fusion of vertebrae, a con- 

 dition probably due to the multiplicity of movement involved 

 in the varied life of the rabbit. 



The pectoral girdle consists of a small vestigial clavicle 

 connecting the sternum with the second element or scapula. 

 This is a large, triangular, flat bone with a glenoid cavity at 

 one angle. Down the centre of one surface is a ridge or 

 spine, culminating towards the glenoid cavity in an acromion 

 process which usually has a backwardly projecting part 



