42 



THE SKELETON. 



The superior articular processes are concave, and look backward and inward ; 

 the inferior, convex, look forward and outward ; the former are separated by a 

 much wider interval than the latter, embracing the lower articulating processes 

 of the vertebra above. The transverse processes are long, slender, directed trans- 



Superior articular process. 



-Lumbar vertebra. 



versely outward in the upper three lumbar vertebrae, slanting a little upward in 

 the lower two. They are situated in front of the articular processes, instead of 

 behind them as in the dorsal vertebras, and are homologous with the ribs. Of the 

 three tubercles noticed in connection with the transverse processes of the twelfth 

 dorsal vertebra, the superior ones become connected in this region with the back 



Inf. articular process. 



Costal process. 



Mammillary process. 

 Accessory process. 



Sup. articular process 



FIG. 8. Lumbar vertebrae. 



part of the superior articular processes, and have received the name of mamniillary 

 processes ; the inferior are represented by a small process pointing downward, 

 situated at the back part of the base of the transverse process, and called the 

 accessory processes : these are the true transverse processes, which are rudimental 

 in this region of the spine; the external ones are the so-called transverse processes, 



