TEE VERTEBRA. 



39 



The transverse proceBsea incline very much forward and downward ; tliey become longer from 

 the first to the Becoiul-last bone ; in the latter tliey become contracted, and in the seventh 

 vertebra tliey are still more diminished, and terminate in an obtuse point. The tubercle of the 

 anterior articular process is extremely prominent, iin<l the posterior notches are surmounted by 

 a small, very acute prolongation, directed backwards, which becomes more developed towards 

 tlie anterior vertebrae. This small prolongation exactly repreaenta tlie transverse process of the 

 dorsal vertebrae. 



E. Rabbit.— They are stronger than those of the Cat, and the first three have on the lower 

 surface of their bodies a very salient crest, which simulates a real inferior spine ; the others 

 have a median crest which gradually decreases towards the last bone. The tubercle surmount- 



Fig. 24, 



LUMBAR VERTEBRAE OF THE CAT AND RABBIT. 



A, Second, third, and fourth lumbar vertebra of the Cat (inferior face}. 1, 1, 1, 

 TraDsverse processes ; 2, 2, 2, ciest on the inferior face of the body ; 3, articular 

 tubercles of the first vertebra. 



B, Second, third, and fourth lumbar vertebrcE of the Rabbit (inferior face). 1, 2, 

 Same signification as in preceding. 



C, Third lumbar vertebra of the Cat (lateral face). 1, Transverse process, anterior 

 prolongation; 2, ditto posterior prolongation; 3, 3, anterior articular tubercles; 

 4, 4, posterior ditto; 5, spinous piocess. 



D, Third lurnbar vertebra of the Rabbit (lateral face). 1, Transverse process, anterior 

 prolougntion ; 2, ditto posterior prolongation; 3, anterior articular tubercle; 

 4, 4, posterior articular tubercles : 5, spinous process. 



ing the posterior notches is more developed than in the Cat. The spinous process is prolonged 

 backward by a translucent bony plate, which disappears in the last two. The anterior articular 

 tubercles are more developed, more erect, and nearer the median line, than in the Caruivora. 

 Lastly, the transverse processes are relatively longer, and those of the first are remarkable for 

 the notched enlargement they ofifer at their free extremities. 



4. Sacrum (Fig. 25). 



The sacrum results, as already stated, from the consolidation of five vertebne. 

 This single bone articulates, in front, with the last lumbar vertebra ; behind, 

 with the first coccygeal bone, and on the sides with the ossa innominata. It is 

 triangular, flattened above and below, and from before to behind describes a 

 shght curve upwards. It offers for study a superior and an inferior fare, two 

 lorders, a lase, a summit, and a central canal — the extension of the spinal canal. 



Faces. — The superior face presents, on its middle, the spinous processes of the 



