CAUDAL VERTEBRA. 



[CHAP. 



being raised on pedicles), and well-developed single transverse 

 processes. But a gradual change takes place in these 

 characters (see Figs. 27 and 28), the body lengthens out and 

 becomes more and more cylindrical ; the neural arch 

 diminishes and finally disappears, leaving for a while a pair 

 of processes at each extremity of the vertebra, the remains 

 of the parts of the arch which bore the zygapophyses ; the 

 transverse process is much reduced, and confined to the 



m 



FIG. 27. Anterior surface of twelfth 

 caudal vertebra of Leopard, . _ in 

 metapophysis ; p processes serially 

 continuous with those which support 

 the posterior zygapophyses in the an- 

 terior vertebrae; ; // hypapophyses. The 

 process on the side of the body be- 

 tween m and h is the anterior trans- 

 verse process. 



FIG. 28. Upper surface of twelfth caudal 

 vertebra of Leopard, . m metapo- 

 physes ; p processes serially continuous 

 with those which support the posterior 

 zygapophyses in the anterior vertebrae. 

 t transverse process ; t' anterior trans- 

 verse process. 



posterior extremity of the body, a second one appearing at 

 the anterior extremity. Even these rudiments of processes 

 gradually cease to be perceptible, and nothing is left but a 

 cylindrical rod of bone, representing the centrum alone of 

 the vertebra. These diminish in size towards the apex of 

 the tail, the last being usually a mere rounded nodule. 



Connected with the under-surface of the caudal vertebrae 

 of many animals which have the tail well developed are 



