42 THE FROG 



259. Levator scapulae superior, lateral to the rhom- 

 boideus anterior. Origin from the prootic, and 

 squamosal: insertion on ventral surface of supra- 

 scapula. 



260. Levator scapulae inferior, lateral and ventral of 

 the rhomboideus anterior. Origin from occipital: 

 insertion on ventral surface of suprascapula. 



261. Cucularis, at the lateral margin, a long thin muscle. 

 Origin from prootic and occipital: insertion on 

 cephalic margin of scapula. Note between the 

 cucularis and the depressor mandibulae the thymus 

 gland (130). 



Pull the latissimus dorsi caudad and lift suprascapula, 

 exposing 



262. Rhomboideus posterior at the mesial border. Ori- 

 gin from 3d and 4th vertebrae: insertion on supra- 

 scapula. 



263. The serrati, three small muscles arising from the 

 3d and 4th vertebrae, two of which insert on the 

 suprascapula, and the third on the scapula. 



Drawing 20. Complete sketch of dorsal body mus- 

 culature (x2). 



Turn the frog ventral side uppermost and identify thei 

 following muscles, commencing a sketch as before: 



264. The submaxillaris, uniting the halves of the lower 

 jaw. 



265. Subhyoideus, immediately caudad. Origin from the 

 hyoid: insertion on lower jaw. 



266. Extending caudad from beneath the submaxillaris, 

 the geniohyoideus on each side of the mid-line. 

 Origin from lower jaw: insertion on hyoid. 



