THE SPINE. 85 



The three lower dorsal vertebrae approach in the form of their 

 bodies to those of the loins. Frequently, but- not always, the 

 tenth has the articular face for the head of the rib, equi- distant 

 from its upper and lower margins, and its transverse process so 

 short, and inclined backwards, that the tubercle of the tenth rib 

 does not form an articulation with it. The eleventh and twelfth 

 vertebras have also the fossae for the heads of the ribs, in their 

 middle, at the sides of the roots of the processes; instead of a 

 partial pit at their upper and lower margins. Their transverse 

 processes are remarkably short, are directed almost backwards, 

 and do not touch the ribs, and have therefore no articular marks. 

 The spinous process departs from the triangular shape, becomes 

 flattened and vertical at its sides, is not far from being horizon- 

 tal, and has a tubercle at its extremity. 



The middle vertebrae of the back have some minute points of 

 difference among themselves, the most of which it would be 

 useless to study. They increase, as stated, gradually in size as 

 they descend, and their spinous processes are very near to, and 

 overlap each other, like shingles on the roof of a house. 



Of the Lumbar Vertebra. 



Common Characters. Their number has been stated at five. 

 Their bodies are larger than those of the other true vertebrae, 

 and are oval on the upper and lower surfaces, with the long di- 

 ameter transverse. The epiphyses at the margins of these 

 faces, are larger and more elevated. The spinal foramen is 

 triangular and more capacious than in the dorsal vertebrae. 

 The inter-vertebral notches for the nerves to pass out, are much 

 larger than elsewhere in the spine, and are formed principally 

 by the upper of the two contiguous vertebrae, though the diffe- 

 rence is not very remarkable. 



The transverse processes are very long, and stand out at right 

 angles. The articular faces of the upper oblique processes are 

 concave and vertical, being directed very much inwards, or 

 looking towards each other; the lower oblique processes are 

 convex, and have the articular faces directed very much out- 

 wardly. The spinous process is short, thick, and horizontal; 

 having broad, flat sides, and terminating by an oblong tubercle. 



VOL. I. 8 



