MYOLOGY OF REPTILES. 



223 



and abdominal ril)s : its inyoconnual ,se])ta describe an acute angle 

 directed backward. At tlie l^ase of the tail it descends to tlie 

 lower border, and covers part of the third muscular column. 

 This derives a tendinous origin from the inner trochanterian ridge 

 of the femur, and from a ligament thence extending to the femoro- 

 fibidar articidation : from those attachments the muscle passes 

 l^ackward to the haemal arches and spines related thereto by 

 alternating origins and insertions, and there assumes the myocom- 

 nial character of the lowest or hasmal tract in the tail of the Newt 

 and Fish. By its anterior attachments in the Crocodile, this series 

 of muscles — t\\efemoro-j]ero7ieo-(:occy(iiuii of Cuvier — closely asso- 

 ciates the pelvic limljs with the tail in the natatory actions and 

 evolntions of the amphibious carnivore. 



The mandiljvdar muscles are strongly dc^•cloped m the Cro- 

 codile in comparison 



with other Saurians ; 112 



although they seem, 

 after a comparison with 

 those of carnivorous 

 mammals, small in pro- 

 portion to the length 

 and massiveness of the 

 jaws. The temporal 

 is represented by two 

 muscles, one of which, 

 the pretemjjoralis, fig. 



142, e, has its origin extended forward into the orbit from 

 lieneath the })Ostfrontal, whence its fibres pass oljliquely l^ack- 

 ward : the larger temporalis, ib. f, is attached to the parietal, 

 the mastoid, and tympanic, and its fibres pass vertically external 

 to those of the pretemporal, to be inserted into the coronoid and 

 surangular. The pterj/goidei are larger muscles than the tem- 

 porales ; the one from the ectopterygoid, fig. 142, /«, receives 

 an accession of fibres from the long pterygoid bone, and, 

 passing obliquely backward, swells out into almost a hemi- 

 spheric prominence at its insertion into the outer side of the 

 angxdar elements at li. The apiertor oris, or dhjnatric, ib. r/, arising 

 from the back part of the prominent mastoid, descends obliquely 

 backward to the projecting angular process behind the tympano- 

 mandibular joint. When the mandible rests on the bank, as at 

 «, a, supporting the head of the crocodile, and makes its angles, 

 ib. 29, the fixed point, the digastrici, g, acting upon the lever of the 

 mastoid, 8, open the mouth l^y rotating the cranium and upper 



JkiiidibiiLir muscles, GrocodiJe 



