PHYLUM CHORDATA 



275 



end attached to the foot the insertion. According to their action 

 muscles are divided into flexors which bend, and extensors which 



. ( .:>s. Rana esculenta. The muscles from the ventral aspect. On the left side (right of 

 figure) many of the superficial muscles have been cut and reflected to show the deep layer. 

 add. brev. adductor brevis ; add. long, adductor longus ; add. mag. adductor magnus ; del. del- 

 toid ; ext. cr. extensor cruris ; ext. trs. extensor tarsi ; FE. femur; gn. hy. genio-hyoid ; 

 r/str. gastrocnemius ; liy.gl. hyoglossus ; ins. ten. inscriptio tendinea ; I. alb. linea alba ; 

 iiiy.hy. mylo-hyoid ; obi', int. obliquus interims ; obi. ext. obliquus externus ; o.st. omosternum ; 

 p. c. hy. posterior cornu of hyoid ; pet. pectoralis ; pctn. pectineus ; per. peronaeus ;, ret. abd. 

 rectus abdomiiiis ; rect. int. maj. rectus interims major ; rect. int. min. rectus intern us minor ; 

 sar. sartorius ; sb. mt. sub-mentalis ; sem. ten. semi-tendinosus; tib. ant. tibialis anticus; tib. 

 post, tibialis posticus ; XT. FI. tibiofibula ; vast. int. vastus interims ; x. st. xiphisterimm. 



