MUSCLES OF THE BODY. 



135 



Action. Raises the snout. 



M. rectus capitis posterior medius (Fig. 71, d). (This 

 is in man a part of the rectus capitis posterior major.) It lies 

 beneath the rectus capitis posterior major (Fig. 71, a). 



FIG. 71. DEEP MUSCLES OF THE NECK, AFTER THE REMOVAL OF MM. BIVENTER 



CERVICIS AND COMPLEXUS. 



0, M. rectus capitis posterior major; b, M. obliquus capitis inferior; f, M. semi- 

 spinalis cervicis; d, M. rectus capitis posterior medius;^, M. obliquus capitis superior; 

 f, M. longus atlantis; g, M. scalenus (part of cervical portion); h, cut end of M. 

 levator scapulae. 



Origin from the cranial end of the axial spine. It forms a 

 triangular prismatic mass which passes craniad and has its 



Insertion into an elongated area on the occipital bone, 

 ventrad of the median half of the lambdoidal crest. 



Relations. Dorsal surface with the rectus capitis posterior 

 major (Fig. 71, a). Ventral surface with the atlas and the 

 rectus capitis posterior minor. 



Action. Assists the rectus capitis posterior major. 



M. rectus capitis posterior minor. A small triangular 

 muscle beneath the rectus capitis posterior medius (Fig. 71, d}. 



Origin by the apex of the triangle from the cranial border 

 of the dorsal arch ol the atlas for about two millimeters laterad 

 of- the median line. The muscle passes over the ligament 

 which connects the atlas to the occiput and adheres to it. 



Insertion into an elongated area on the occipital bone, 



