VERTEBRAL COLUMN. 



Fig. 11 



LI 



CO/ 



the column had the usual direction, and in which 

 the right arm was more muscular than the left. 

 (" Seltene Beobachtungen," part 2, p. 61 ; see also 

 K. Quain, "Anatomy of the Arteries," p. 19.) 



Fig. 11. VERTEBRAL COLUMN OP AN ADULT MALE, 



SEEN FROM BEHIND. 



C 1 to above D 1, the seven cervical vertebrse ; 

 D 1 to above L 1, the twelve dorsal vertebrse; L 1 

 to above S 1, the five lumbar vertebrse ; S 1 to above 

 CO 1, tbe sacrum ; CO 1, and below, the four 

 coccygeal vertebrse. The attention of tbe reader is 

 called to the transition in the form of the transverse 

 processes and tubercles indicated in this specimen, 

 which is well marked. 



FORM. On the anterior aspect of the 

 column, the pillar formed by the bodies of 

 the vertebrae is seen to become broader from 

 the axis to the first dorsal vertebra. At this 

 place it ceases to widen, and even becomes 

 slightly narrower from the first to about the 

 fourth dorsal vertebra ; from that level it then 

 becomes gradually wider down to the base of 

 the sacrum. The width between the extremi- 

 ties of the transverse processes is considerable 

 in the atlas ; it is small in the axis, becomes 

 greater as far as the first dorsal vertebra, 

 thence it is again gradually contracted as far 

 as the last dorsal, and becomes suddenly much 

 greater in the lumbar region. 



On the lateral aspect, the diameter of the 

 bodies from before backwards is seen to in- 

 crease most rapidly in the dorsal region. The 

 tips of the transverse processes of the dorsal 

 vertebrse, being directed backwards, describe 

 a greater curvature than the bodies ; while 

 the spinous processes exhibit a smaller curva- 

 ture, on account of the middle dorsal set being 

 most sloped downwards, while those above and 

 below project backwards. 



On the posterior aspect, the spines occupy 

 the middle line. Those of the dorsal region 

 are in many instances inclined a little, some 

 to one side and some to the other. At the 

 sides of the row of spines are the vertebral 

 grooves, corresponding to the laminae, and 

 bounded externally in the cervical and dorsal 

 regions by the transverse processes, and in the 

 lumbar by the mammillary processes. They 

 are broad but shallow in the neck, and become 

 deep and narrow lower down ; the narrowest 

 part being at the last dorsal vertebra. Along 

 the grooves is a series of spaces between the 

 laminae, which, in the natural condition, are 

 filled up by the yellow ligaments. The extent 



