460 ANATOMY OF VERTEBRATES. 



the fore part of the base of the neurapophysis, as shown in the 

 longitudinal section, fig. 308.^ The costal part of the transverse 

 process is large and lamelliform in the fourth to the sixth cer\dcal 

 vertebrae inclusive : in the seventh it is a short protuberance : in 

 ^ „ this cervical the neural sijine be- 



3(38 . ^. 



comes conspicuous. Ihe metapo- 

 physial tubercle is developed from 

 the diapophysis in the eleven ante- 

 rior dorsal vertebra, and passes upon 

 the zygapophysis in the twelfth, con- 



Section of third cervical, Camel. ,. . . ,i, •■• ,i ^ . 



tmumg m that position throughout 

 the lumbar series. There are no anapophyses. The spinous pro- 

 cess in the first dorsal suddenly exceeds in length that of the last 

 cervical, and increases in length to the third dorsal ; from this to 

 the twelfth dorsal the summits of the spines are on almost the same 

 horizontal line, and are expanded and obtuse above, sustaining 

 the substance of the hump (Dromedary) or humps (Camel) ; the 

 spines of the lumbar vertebrje progressively decrease in length. 

 The diapophyses of the last six lumbar vertebrae are very long : 

 those of the last lumbar do not articulate, in the Camelidce or in 

 any Ruminant, with the sacrum. 



In the Llama {Auchenia) the last sterneber is not so expanded 

 as in the Camel : the vertebral formula is the same : the fifth 

 lumbar has the largest spine : the cervicals, besides ha\dng im- 

 perforate transverse processes, resemble those of Macrauchenia 

 in the flatness of the terminal articular surfaces, and the neck is 

 habitually less bent down than in the Camels. 



In the Musk-deer {^Moschns moschiferus), the vertebral formula 

 is: — 7 cervical, 14 dorsal, 5 lumbar, 5 sacral, and 6 caudal. The 

 atlas has a hypapophysis, but no neural spine. The transverse 

 process is a broad thin plate coextensive with the length of the 

 vertebra : it is perforated transversely from the neural canal 

 outward to beneath its base, for the exit of the nerve, and then 

 vertically, by the vertebral artery, which also perforates the 

 neural arch. The axis has a sharp hypapophysial ridge extending 

 from below the base of the odontoid process to beyond the poste- 

 rior surface of the centrum, where it underlaps the next vertebra. 

 A similar ridge and backwardly produced process are developed 

 from the two succeeding cervicals, beyond which the ridge gra- 

 dually subsides to the seventh vertebra. From the third to the 

 sixth cervical inclusive, the pleurapophysial part of the transverse 



' XCII-. p. 218, no. 925, a., figured in xcv. pi. vi. fig. 2, also in xcvi, fig. 344. 



