44 THE FROG 



275. the stemohyoideus with origin from the sternum 

 and insertion on the hyoid. 



276. The omohyoideus with its origin on the scapula and 

 insertion on the hyoid. In the angle formed by these 

 muscles as they converge towards the hyoid, note the 

 parathyreoids (128). 



Cut through the steiifiohyoideus and observe: 



277. the petrohyoidei, four small muscles from the audi- 

 tory capsule (225) to hyoid. Note in the notches of 

 the hyoid, close to the origin of the hyoglossals, the 

 thyreoid glands (129). 



Open the jaws widely, remove the skin from the mouth and 

 identify the temporalis (249) and the following: 



278. pterygoideus. Cephalad and mesiad of the tem- 

 poralis. Origin from the fronto-parietal and prootic: 

 insertion on lower jaw. 



279. The masseters, two small muscles of which one runs 

 from the cephalic border of the tympanum to the 

 angulare, concealing the other which connects the 

 quadrato-jugal with the angulare. 



Drawing 21. Complete drawing of ventral body 

 musculature (x2). 



The Muscles of the Hind Leg 



Place the frog ventral side up and identify the following 



muscles, making a sketch as you proceed. 



In the thigh, commencing at the lateral margin: 



280. Triceps femoris. This great muscle has three ori- 

 gins; the caput anticum from the cephalic margin 

 of the acetabulum (244), caput medium from the 

 ilium, and caput posticum from the same bone at 

 the caudal end: insertion on tibio-fibula. 



