

514 



2977. The atlas. 



The hypapophysis developes a process from the lower part of the anterior surface. The 

 neural arch is perforated transversely hy the vertebral artery. 



2978. The axis. 



The centrum supports a simple diapophysis, inclining downwards and backwards. The 

 neural spine is thick, short, tuberculated, and divided by a deep and broad groove into two 

 the upper part of the spine is prolonged obliquely upwards, giving the whole a trifid 

 character. 



2979. The third cervical vertebra. 



The pleurapophysis is inclined downwards and backwards, expanding into a broad plate. 



2980. The fourth, fifth and sixth cervical vertebrae of the same Rhinoceros. 



The pleurapophysial plate increases in size to the sixth vertebra. The diapophysial portion 

 of the transverse process bends backwards and upwards. 



2981. The seventh cervical vertebra. 



The neural spine, which has been progressively increasing in length from the third vertebra, 

 now -becomes long and pointed. The transverse process is a simple diapophysis. The sutures 

 are still persistent, dividing the centrum from the neural arch and diapophyses. 



2982. The nineteen dorsal vertebrae. 



A metapophysis is developed in the fourth dorsal from the back part of the diapophysis ; 

 it continues throughout the series, and becomes distinct from the diapophysis in the sixteenth 

 dorsal. The first dorsal spine is almost vertical ; the third is the longest ; they then decrease 

 to the tenth, from which their length or height does not exceed their antero-posterior extent, 

 until the sixteenth, when they again lengthen. 



2983. The three lumbar vertebrae of the same Rhinoceros. 



The diapophysis appears suddenly in the first ; it becomes shorter in the second ; and still 

 more so in the third, in which it is very strong and broad. The lower edge of the diapo- 

 physis of the second lumbar articulates with the upper edge of the diapophysis of the third, 

 and the third articulates in the same manner with the first vertebra of the sacrum. The 

 metapophyses are distinct, and are situated on the anterior zygapophyses in the first two 

 lumbars : in the last they have become rudimental, and almost obsolete. 



