358 



MANUAL OF ELEMENTARY ZOOLOGY 



a-b.a. 



Fig. 257. — The forepart^of the body of a dogfish, dissected to show 

 the heart and ventral arterial system. 



a.,/>,a. f Afferent branchial arteries; au., auricle ; c.a., conus arteriosus; c/t., cera- 

 tohyal cartilage; d.C, ductus Cuvieri ; jg-., gills ; ^.c. gill clefts ; 1.0., internal 

 opening of the first gill cleft ; l.s,, line of section in Fig, 268, which should he 

 compared; M.c. t Meckel's cartilage; ?««., muscles from coracoid __ region of 

 shoulder girdle to various parts of visceral skeleton ; _/»*., pericardium; j.w., 

 sinus venosus; se. t scapula; thy., thyroid gland (displaced); z>., ventricle 

 V.ao.. ventral aorta. 



