GENERAL BIOLOGY 



The mouth or oral opening is relatively large. The opening on the in- 

 terior is called the buccal ( ) cavity. There are 

 teeth on the maxilla ( ), premaxilla ( ), 

 and vomer bones ( ). These assist in holding, but 



Fig. 6. A Male Frog Dissected from the Ventral Side. 



a.ab.v., Anterior abdominal vein, cut short, ligatured, and turned back ; a.musc., 

 cut edge of abdominal muscles ; bl., urinary bladder ; c.d., common duct of gall- 

 bladder and pancreas ; d.ao., dorsal aorta ; du., duodenum ; f.b., fat body ; fem.v., 

 femoral vein ; g.b., gall-bladder ; ht., heart ; hy.n., hypoglossal nerve ; im., ileum ; 

 i.v.c., inferior vena cava ; k, kidney ; k.d. kidney duct with vesicula seminalis ; 

 lr., liver ; o, point at which c.d. enters the duodenum ; pcs., pancreas ; pl.v., pelvic 

 vein ; r.L, right lung ; rm., rectum ; r.p.v., renal portal vein ; sar., sartorius muscle ; 

 sm., mylohyoid muscle ; sp., spleen ; st., stomach ; t., testis ; v.v., vesical vein. (After 

 Borradaile. ) 



not in masticating the food. Immediately back of the tongue on the 

 floor of the mouth is a narrow slit called the glottis ( ) 



leading to a tube passing to the lungs, and directly behind the glottis, 



