242 



ANATOMY OP VERTEBRATES 



interosseus cruris, fig. 158, 120, extends obliquely between the 

 opposite margins of the leg-bones. The mterossei digitorum 



158 



Musrlcs of liilld-foot, Emits Europ^ra. xxxvill. 



dvrsah's, are shown at 122, and those of the plantar surface at 123, 

 fig. 158. 



The highest faculty of terrestrial locomotion in the reptilian 

 class, is manifested by the saltatory batrachians. 



In the hind limlj of the frog tliere is a muscle which extends 

 from the diapophysis of the third vertclira to the ilium, which it 

 tends to protract, and acting from which it may slightly Ijend the 

 back. Tlie ccUxjlutnis receives an accessory strip from the 

 coccygeal style. The mesot/hifeiis is a strong muscle. The entn- 

 (/luteus and iliacus are united. The ohturator e.rternus has a semi- 

 circular form. The quadratiis femoris is in two strata. There 

 are Uvo pcctinei and four addiictores femoris. Tlie extensor cruris 

 consists of a vdstus internus and a vastus e.rternus with a coalesced 

 crurcEtis; there is no rectus feumris. T\\e Jicror cruris has l.nit 

 one head or origin from the lower and back part of the ilium. 

 The semitcndinosus has two heads, one from the fore part, the 

 other from the back part of the ischio-pubic symph\-sis. The 

 seuiiniemhranosus and (p'acilis have the usual attaclnncnts. The 

 sartor/us resembles the rectus in its position and course in front of 

 the thigh: it is united to tlie feasor fa seiee lata-. The gastro- 

 cnemius is represented by its external moiety, which is so large as 

 to give the a])i)earancc of a ' calf " to tlie leg: its tendon glides 

 behind the tibio-larsal joint, and expands as it descends along 

 the tarsal segment into a plantar fascia. The tihialis autieus 

 arises by a strong tendon 1'rom the fonuir, and divides at the 

 middle of the tibia into a fascicle inserted into the astragalus, and 

 a second inserted into tlie calcanemu ; in both at tlie proximal 

 end. A eruro-tdiinHs rises from the lower end of the femur, and 



