228 Zoology and Comparative Anatomy '■ 



three lateral processes of the first three bones of the neck, 

 (" Forme par des apophyses laterales des trois premieres cer- 

 vicales." Dubar.) This, it is to be observed, is only a suppo- 

 sition of the superintendent of the dissection, M. Dubar, who 

 states that the soft parts were in such a state of decomposition, 

 that it was almost impossible -to distinguish it. The true 

 spinal canal commences at the fifth cervical vertebra, and 

 extends nearly to the last caudal vertebra, being lost at the 

 fifty-fourth. 



This canal is formed of a triangular shape, by a series of 

 spinous processes which make the arch on the bodies of the 

 bones composing the spine, for the reception of the spinal 

 marrow. 



The Atlas, or thejirst Bone of the Nech — The anterior sur- 

 face presents two articular fossae [cavities] for the reception 

 of the condyloid processes [knobs] of the occipital bone, and 

 is the means of the head articulating upon the trunk ; supe- 

 riorly and laterally there are two canals capable of receiving 

 the human little finger, which give passage to the vertebral 

 vessels. The two transverse processes are tuberose and 

 asperated [roughened], for the attachment of the adjacent 

 muscles and lateral ligaments, permitting the head to perform 

 the various motions intended for it by the great Author of 

 nature. The posterior surface of this bone exhibits nothing 

 beyond a few irregularities by which it is attached to the bone 

 behind it. There is no hole or foramen in the transverse 

 process of the atlas, for the passage of blood-vessels and 

 nerves. 



The second Bone of the Spine is of a curious yet regular 

 shape, presenting an oval figure, the great diameter of which 

 is transverse. This bone has no spinous, but has two enormous 

 transverse processes; each of which possesses a very large- 

 foramen, which exceeds that of the occipital bone by twice its 

 diameter. The third, fourth, and fifth cervical vertebrae have 

 double transverse processes, so that they do not, as in the 

 second, form a complete foramen or hole ; and the fifth exhi- 

 bits the rudiments of a spinous process. The sixth forms a 

 curve on its body, that, when united, has its convexity down- 

 wards. 



The Bones of the Back. — These are fifteen in number, 

 although the ribs are but fourteen on each side ; the first of 

 which, being bicipital [two-headed], is united to the first two 

 dorsal vertebrae. The transverse processes have at their ex- 

 tremity an articulating surface for the union of the ribs — a 

 phenomenon peculiar to these animals ; and, consequently, the 

 motions of the ribs must be somew^hat limited. The bodies and 



