Relations.—Ventral surface with the longus capitis (a). Dorsal surface with the anterior (ventral) atlanto-occipital membrane (2).
Action.—Depresses the snout.
[Fig. 72].—Muscles on the Ventral Surface of the Cervical Vertebræ.
![[Fig. 72]](#3418956513767812439_illo143lg.jpg.id-7027977754275173225.wrap-0.html.html){kind=link}
On the left side the longus capitis and one head of the levator scapulæ ventralis have been cut, in order to show the rectus capitis anterior minor. a, M. longus capitis; b, M. rectus capitis anterior minor; c, M. levator scapulæ ventralis (c′, its atlantal head; c″, its occipital head); d, M. rectus capitis lateralis; e, M. obliquus capitis superior; f, M. longissimus capitis; g, M. longus colli (g′, its cervical portion; g″, its thoracic portion); h, part of M. scalenus. 1, bulla tympani; 2, ventral atlanto-occipital membrane; 3, ventral arch of atlas; 4, first rib.
M. rectus capitis lateralis ([Fig. 72], d).—This lies ventrad of the obliquus superior (e) on the ventral face of the transverse process of the atlas and at first appears to be a part of the obliquus superior.
Origin from the median half of the ventral surface of the transverse process of the atlas. The fibres form a cylindrical mass which passes craniad and slightly laterad.
Insertion into the fossa laterad of the condyle of the occipital bone.
Relations.—Ventral surface with the digastric ([Fig. 65], b) and the lymphatic gland ventrad of the ear. Dorsal surface with the wing of the atlas.
Action.—Flexes the head laterally.