CHORDATES IN GENERAL 



155 



Buccalcim 



QUI slit in wall 

 J)f pharynx 



Afferent branch- 

 Jal arteries 



I Ventral aorta 



Dorsal aorta 



Notochord 



Spinal cord 



-. Distribution throuqh 



iver 



r 



Hepatic V. 



^ubintestinal vein 

 .Atriopore 



:vi" 



Ventro-'intestinal V. 



Dorso-ints5tinal A. 



</ 



Anus 



Caudal vein 



; Caudal artery 



Fig. 51. — Circulatory system of Amphioxus. 



