MYOLOGY OF REPTILES. 



233 



diapophysis of the atlas : the tendon so inserted is shown at 33, 

 fig. 148. 



The comjrtexus, fig. 148, 23, arises from the diapophyses of the 

 first three cervicals, and is inserted into the paroccipital: in 

 fig. 150, the hindmost origin of this muscle is marked 25. 



The rectus capitis anticus longus, fig. 148, 29, arises from the 

 hypapophyses of the third and second cervicals, and is inserted 

 into the side of the basioccipital. The rectus capitis antictis 

 brevis, fig. 152, 30, arises from the atlantal hypapophysis, and is 

 inserted into the basioccipital. The rectus capitis posticus major, 

 fig. 148, 3i, arises from the neural spines of the axis and atlas, 

 and is inserted into the paroccipital. The rectus capitis posticus 

 minor, ib. 31, arises from the neural arch and diapophysis of 

 the atlas, and is inserted into the base of the exoccipital. 



The largest and most remarkable portions of muscular segments 

 of the trunk are those which are combined to effect the retraction 

 beneath the carapace of the head and neck. The retruhens 



j 49 



Side view of trunk-muscles and deeper seated limb-muscles, Emys Europma. xxxvm. 



capitis collique, figs. 149, 150, 27, arises by six fleshy fasciculi 

 from the neural arches and spines of the eighth to the fifth 

 dorsals inclusive ; these pass forward, blending together, and then 

 detach four tendinous insertions: of these, the anterior and 

 longest, as well as strongest, is into the basioccipital fossa ; the 

 other three are into the diapophyses of the fourth, fifth, and sixth 

 cervicals. It is not difficult to sever the part of the great re- 

 tractor connected with the cervical insertions, as a distinct muscle 

 from that inserted into the occiput. The biventer cervicis, figs. 

 150, 151, 24, arises from the neural spines of the fifth, fourth, and 



