264 SKELETON OF THE BABBIT 



ii, The neurapophyses are lower than in the anterior 



vertebrae, but longer from before backwards, 

 iii. The transverse processes are placed further 



back, and have no articular facets for the ribs, 

 iv. Metapophyses appear in the ninth thoracic 



vertebra, and increase considerably in size in 



the succeeding ones. 



4. The lumbar vertebrae. 



These are usually seven in number: the most 

 anterior one may, however, bear ribs, in which case 

 it is reckoned as a thirteenth thoracic vertebra, and 

 the lumbar vertebrae become reduced to six. 



The characters of a typical lumbar vertebra have 

 already been described : as a group they are charac- 

 terised by their large size, and the great development 

 of their processes, especially the transverse processes. 

 They increase in size from before backwards, the last 

 but one being the largest. The first two have hyp- 

 apophyses : the last one has a short stout centrum, 

 and a stout crest-like neurapophysis. 



5. The sacral vertebrae. 



Strictly speaking, the sacral vertebrae are those 

 of which the expanded ribs directly support the pelvis ; 

 and of these the rabbit has only one, or at most two. 

 A certain number of the succeeding vertebra?, which 

 are fused with one another and with the last true 

 sacral vertebra, are, however, commonly included 

 under the same name, the whole fused mass being 

 spoken of as the sacrum. Beckoned in this way the 

 rabbit has four or more sacral vertebrae, the lines of 

 boundary between which can easily be made out, in 

 spite of their fusion. 



a. The first sacral vertebra is much the largest, and is 

 produced laterally into a pair of large wing-like 

 expansions which support the pelvis, and are re- 

 garded as modified ribs fused with the vertebra. 

 The neurapophysis is large and nearly vertical. 



