MORPHOLOGY OF CKAXIAL MUSCLES IX SOME VERTEBRATES. 219 



hyoideus gains a new insertion to tlie hind end of the lower 

 jaw. The cerato-hjo-angularis, suspensorio-angularis^ a!id 

 quadrato-angularis assume a more vertical position on the 

 rotation of the palato-quadrate, and form the inner portion, 

 whilst the original orbito-hyoidens forms the outer portion, 

 of the depressor mandibulas. 



The interhyoideus of the larvee of Rana^ forms a transverse 

 band connecting together the two ceratohyals (Text-fig. 57), 

 and this is also the case in Alytes. In Pelobates and Bufo 



Text-fig. 48. 



UAT.Vvi 



Sco4> 





lentiginosus it extends backwards below the branchial 

 cavity, iind this hinder part forms the sub-branchialis (of 

 Schultze), and the diaphragmato-branchialis (of Schultze) is 

 separated from the median edge of this muscle. 



The digastric muscle" of Mammals is either monogastric 

 (digastricus spurius), inserted into the jaw, or digastric 

 (digastricus verus), with a tendon between the two bellies 

 which niay or may not be connected with the hyoid bone. 



' Siibhyoideus of Ecker and Gaiiii. and of Schultze. 

 - This bare outline only is given, as the matter has been so thoroughly 

 disciissed by Bijvoet. 



