54 ANATOMY OF THE WOOD RAT 



The deep short system of the deep back musculature is 

 composed of seven muscles as follows: 



Mm. transversospinales obliquus capitis superior 



rectus capitis posterior major obliquus capitis inferior 



rectus capitis posterior minor longus atlantis 

 rectus capitis lateralis 



Mm. transversospinales occur in bundles, connecting each 

 vertebra with the transverse processes or diapophyses, 

 as the case may be, of the one next craniad. These really 

 include the interspinals as well, but the fibers are ex- 

 tremely involved and difficult to segregate with precision. 



This series is innervated by branches from the spinal 

 nerves. 



M. rectus capitis posterior major (figs. 11, 24) has origin 

 from the lateral surface of the spine of the axis. In- 

 sertion is upon the supraoccipital from the rectus fossa 

 laterad to the latero-caudal process of the occiput. 



M. rectus capitis posterior minor (fig. 24) is situated 

 medio-ventrad (deep) to the last. Origin is from the medial 

 portion of the atlas, and insertion is upon the supraoccipital 

 from the medial ridge laterad to the rectus fossa. 



M. rectus capitis lateralis (figs. 8, 11, 24) has origin 

 from the cranial part of the transverse process of the atlas, 

 with insertion upon the slight extension of the angle of the 

 occiput running ventrad from the process at its infero- 

 lateral end. In Teonoma this muscle seems to be not so 

 well developed. 



M. obliquus capitis superior (figs. 8, 10, 11, 24) has 

 origin from the ventral border of the transverse process of 

 the atlas, with insertion upon the exoccipital mediad to the 

 mastoid and the caudal face of the paroccipital process. 



M. obliquus capitis inferior (fig. 11). Origin is from 

 the caudal half of the lateral surface of the spine of the 

 axis, with insertion along most of the dorsal surface of the 

 transverse process of the atlas. 



