ANUEOSOEEX. 155 



Vertebral column, — There are 15 dorsal, 6 lumbar, 5 sacral, and 9 caudal 

 vertebrae. The spinous process of the axis has considerable antero-posterior exten- 

 sion, is posteriorly falcate, and overreaches the very small spinous process of the 

 third cervical vertebra. The remaining cervical and dorsal vertebrae may be said 

 to have no spinous processes, the indications of their existence are so feebly de- 

 veloped. Traces of them, however, can be observed in the sixth and seventh cervical 

 and on the first to the fifth dorsal, the neural arches of which are quite as narrow 

 rods as those of the former vertebrae, in which they appear as minute processes 

 in the middle of the hinder margin of the arch. In the seventh to the ninth 

 dorsal, the neural arches of which have much more antero-posterior expansion 

 than those preceding them, the obscure representatives of the spinous processes are 

 not more developed, but there is a faint ridge marking the line of union of the 

 laminae. In the tenth to the fifteenth vertebrae, inclusive, there is a rather broad 

 and slightly raised, but flat, roughened surface corresponding to the spinous process 

 on the dorsum of the laminae, broadest in front and rather narrower behind. It 

 becomes most markedly developed in the fifteenth, in which it is narrower than in 

 the preceding, and in the first lumbar it is still more laterally compressed, and in 

 the remaining lumbar vertebrae the spinous process is a thin, low ridge, high in 

 front, but shelving away posteriorly. In the fourteenth dorsal vertebra is the first 

 trace of a process that becomes strongly developed in the lumbar region. It occurs 

 on the dorsum of the posterior zygapophysis, and, on the lumbar vertebrae, becomes 

 a marked process connected by a ridge to the side of the spinous process, and would 

 therefore seem to be the equivalent of a hyperapophysis. 



The transverse process of the atlas is a small thin plate only, slightly projecting 

 beyond the outer margin of the condylar facet. In the axis, it is a small, back- 

 wardly projecting process, perforated at its base by the vertebrarterial canal. The 

 transverse processes increase in length to the fifth vertebra, but in the sixth and 

 seventh they are shorter. To the fifth vertebra the process is directed backwards, 

 but in the sixth it is placed outwards, bringing its extremity in close contact with 

 the process before it, and in the seventh it is outwards and slightly backwards. The 

 pleurapophysial processes of the fourth and fifth cervicals are longest in the former 

 and shortest in the latter, and are directed very much forwards, but slightly 

 downwards. The same process of the sixth vertebra has great antero-posterior 

 extension, being as long as the combined centra of the sixth and seventh cervical 

 and first dorsal vertebrae. Its posterior haH arches below the seventh cervical and 

 the head of the first rib. The transverse processes of the thoracic vertebrae only merit 

 the term of process in the first and second, as in the remaining vertebrae, the rib is 

 apphed directly over the point of union of the pedicle and lamina, without any 

 apparent intervening projection. The outer end of the laminae of the fourth dorsal 

 vertebra above the anterior zygapophyses is capped by a small upwardly and anteriorly 

 projecting process (metapophysis) which attains its greatest development about the 

 seventh or eighth, beyond which it becomes rapidly smaller. The lumbar, transverse 

 processes are mere rudiments and are slightly backwardly projected, without any trace 



