PHYLUM CHORDATA 



255 



limbs. The dorsal muscles of the trunk are no longer divisible 

 into myomeres, but take the form of longitudinal or oblique bands 

 (extensores dorsi, &c.), lying partly above the vertebrae, partly 



FIG. 875. 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 laye*. 

 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-hyoM'; 

 gstr. gastrocnemius ; hy.gl. hyoglossus ; ins. ten. inscriptio tendinea ; I. alb. linea alba ; 

 my.hy. mylo-hyoid; obi. int. obliquus intefnus ; obi. ext. obliquus externus ; o.st. omosternum ; 

 p. c. \y. posterior cornu of hyoid ; pet. pectoralis ; pctn. pectineus ; per. peronseus ; ret. aM, 

 rectus abdominis ; rect. int. maj. rectus internus major ; sar. sartorius ; $b. mt. sub-mentolis ; 

 sem. ten. semi-tendinosus ; tib. ant. tibialis anticus ; lib. post, tibialis posticus ; TI. Fl. tibio- 

 fibula ; vast. int. vastus internus ; x. st. xiphi-sternum. 



