1872.] MR. A. SANDERS ON LIOLEPIS BELLI. 161 



apophysis of the basioccipital in conjunction with the rectus anticus 

 major ; it also receives reinforcements of fibres from the transverse 

 processes of the second and third cervical vertebrae ; some of the 

 lower fibres, derived with the latter from the longissimus dorsi, are 

 inserted with the levator scapulae and cervicalis ascendens into the 

 atlas. 



Trachelo-mastoid (figs. 3 & 4) is the third muscle which is contin- 

 uous with the longissimus dorsi ; it is situated between the two last, 

 and, proceeding straight forward, is inserted into the posterior surface 

 of the exoccipital, external to and behind the articulation of the squa- 

 mosal, exoccipital, and quadrate bones. 



Spinalis dorsi is a continuation forward of the central part of 

 the dorsal half of the caudal muscular mass ; becoming separated 

 at the thirteenth caudal vertebra, it occupies the space between the 

 neural spines and the zygapophyses ; in the dorsal region superficial 

 tendinous slips are developed from the muscular fibres and are in- 

 serted severally into the spines of the dorsal vertebrae : opposite the 

 third cervical vertebra it divides ; the superficial part is continued on- 

 wards, to be inserted into the posterior edge of the parietal and into 

 the supraoccipital close to the middle line internal to the complexus 

 after the manner of a ligamentum nuchae ; the deeper portion ter- 

 minates in three divisions ; the superior is attached to the posterior 

 edge of the neural spine of the atlas, the middle one to the dorsal 

 surface of the posterior zygapophysis of the same vertebra, while the 

 the inferior one is attached to the ventral surface of the zygapo- 

 physis of the same. 



Rectus posticus major (fig. 4) arises from the neurapophysis of the 

 atlas and the neurapophysis and neural spine of the axis, and is in- 

 serted into the supraoccipital beneath the complexus, and also into 

 the posterior border of the exoccipital for nearly its whole length. 



Rectus anticus major (fig. 5) arises from the inferior surface of the 

 centrum and the hypapophysis of the atlas, and from the hypapo- 

 physes only of the vertebrae from the second to the sixth inclusive, and 

 from the centra of the seventh and eighth, and also from the inner 

 surface of the proximal end of the third and fourth cervical ribs, and 

 is inserted into the posterior and inner border of the basioccipital. 



Scalenus anticus (fig. 5). The muscle which appears to correspond 

 to this arises from the centra and the sides of hypapophyses and 

 ventral surfaces of the transverse processes of the axis and two 

 following vertebrae, and is inserted into the first and second cervical 

 ribs and into the centra of the fifth and sixth vertebrae ; at its insertion 

 it is continuous dorsad with the sacro-lumbalis, and posteriorly with 

 the intercostales. ' 



Rectus abdominis (figs. 1, 9, & 10) arises from the base of the 

 xiphisternum for rather more than one third of its extent ; the inner 

 border is attached to that of its fellow of the opposite side throughout 

 its whole length ; posteriorly it is inserted into the ischio-pubic 

 ligament, which in this Lizard has the same attachment as in Gecko, 

 it also gives a muscular slip to be inserted into the hamular process 

 of the pubis, which, I am of opinion, corresponds to the pyramidalis. 



Proc. Zool. Soc— 1872, No. XI. 



