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General Biology 



Innervation : Twig from II spinal nerve. 



(c) Muscles inserted into the shoulder girdle. 



e. g. Levatur anguli scapulae, arising from the skull and in- 

 serted into the under side of the suprascapula, which it draws forward. 

 Innervation : Twig from I spinal nerve. 



Fig. 24. A — A Ventral View of the Muscular System of a Frog. 



ad. long., Adductor longus; ad.mag., adductor magnus; anc, anconaeus; cor.rad., 

 coraco-radialis; dtd., deltoid; e.ob., external oblique; e.cr., extensor cruris ;gast., 

 gastrocnemius; grac, gracilis; I. a., linea alba; pct.ab., abdominal part of the pectoral 

 muscle; pot. St., sternal part of the same; r.ab., rectus abdominis; sar., sartorius; 

 sm., mylohyoid; t.i., tendinous intersections; t.A., tendo Achillis t.f., tibiofibula; 

 tib-ant., tibialis anterior; tib.post., tibialis posterior; v. int., vastus internus; x.c, 

 xiphoid cartilage. (After Borradaile.) 



B. Dissection of special muscles of the left hind leg of the toad (redrawn from 

 Jammes). Muscles shaded in black are extensors, in gray, flexors. 



