LEPUS. 307 
The sacral vertebre are two. They are ankylosed 
together and are firmly joined to the ilium. 
The caudal vertebre vary in number up to fwenty. The 
first few are ankylosed to the sacral vertebree; 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 
Hig. 288.—PrcToraL GIRDLE AND FORE-LIMB OF THE 
Rassit. (4d nat.) 
; B Head. 
Olecranon. 
Spine. 
Radius. 
Acromion. 
e 
Supratrochlear Foramen, 
Coracoid Process. 
A, Scapula. B, Humerus. C, Radius and Ulna. 
the first few caudals, there is no fusion of vertebra, 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 
