410 MUSCLES. 



The Inter-spinales, 



Are small short muscles, placed between the spinous pro- 

 cesses of contiguous vertebrae. In the neck they are double, 

 in consequence of its spinous processes being bifurcated; in the 

 back they are almost entirely tendinous ; in the loins they are 

 single and well marked. 



They draw the spinous processes together, and keep the 

 spine erect. 



The Inler-transversarii, 



Are also short muscles, placed in a similar manner, between 

 the transverse processes of the vertebra?. In the neck they 

 are double, in the back they are small, tendinous, and not well 

 marked ; and in the loins they are single and well seen. 



They draw the transverse processes together, and will, of 

 course, bend the spine to one side. 



The Levatores Costarum, 



Are small muscles concealed by the sacro-lumbalis and lon- 

 gissimus dorsi, and pass from the transverse process of the last 

 cervical and of the eleven superior dorsal vertebrae, to the up- 

 per edges of the next ribs. They are twelve on either side of 

 the spine, are tendinous in their origins and insertions, with in- 

 termediate muscular bellies. 



The upper ones are small and thin. They increase in mag- 

 nitude as they descend. From the inferior edge of nearly all 

 these muscles a fleshy slip is detached, which passes over the 

 rib next below its origin, to the second rib below, and occa- 

 sionally to the third. These slips are called Levatores Costa- 

 rum Longiores. The others, which descend from the trans- 

 verse process to the rib next below, are called Levatores Cos- 

 tarum Breviores. 



These muscles are parallel in their obliquity, with the ex- 

 ternal intercostals, and are not very obviously separated from 

 them. They perform the same service, that of elevating the 

 ribs. 



