MUSCLES OF THE BACK AND NECK. 353 



Inserted into all the transverse processes of the vertebrae of 

 the back, chiefly by small double tendons ; also, by a tendinous 

 and fleshy slip, into the lower edge of all the ribs, except the 

 two inferior, at a little distance from their tubercles. 



Use. To extend the vertebrae, and to raise and keep the trunk 

 of the body erect. 



N. B. From the upper part of this muscle, there runs up a 

 round fleshy portion which joins with the cervicalis descendens. 



3. Sacro-Lumbalis, 



Arises, in common with the longissimus dorsi. 



Inserted into all the ribs, where they begin to be curved 

 forwards, by as many long and thin tendons ; and, 



From the upper part of the six or eight lower ribs, arise as 

 many bundles of thin fleshy fibres, which soon terminate in 

 the inner side of this muscle, and are named musculi ad sacro- 

 lumbalem accessorii. 



Use. To pull the ribs down, and assist in erecting the trunk 

 of the body. 



N. B. There is a fleshy slip which runs from the upper part 

 of this muscle into the fourth, fifth, and sixth transverse pro- 

 cesses of the vertebrae of the neck, by three distinct tendons : 

 it is named cervicalis descendens ; and its use is to turn the neck 

 obliquely backwards, and to one side. 



On the neck are, 



1. Complexus, 



Arises from the transverse processes of the seven superior 

 vertebrae of the back, and four inferior of the neck, by as many 

 distinct tendinous origins ; in its ascent, it receives a fleshy slip 

 from the spinous process of the first vertebra of the back. From 

 these different origins it runs upwards, and is every where 

 intermixed with tendinous fibres. 



Inserted, tendinous and fleshy, into the inferior edge of the 

 protuberance in the middle of the os occipitis, and into a part 

 of the curved line that runs forwards from that protuberance. 

 30* 



