afferent artery 2 



valves 



m-'-^ ...'--"^^'"•--^ _„<3j-anerent arter 

 ^•"^ afferent arter 



afferent artery 4 



afferent artery 5 

 afferent artery 6 



rom sinus venosus 



us venosus 



hepatic veins 



A VENTRAL VIEW 



B DORSAL VIEW 



Figure 11-6. Heart of Squa/us oconfhios as seen from below with ventral wall rennoved, A, ond 

 from above with roof of sinus venosus removed, B. (After Marinelli and Stranger 1959). 



semilunar valve 



ventricle 



truncus arteriosus 



-ight duct of Cuvier, 



nferior jugular 



truncus arteriosus 



ventricle 



atrium 



inferior jugular 



hepatic vein 



sinus venosus 



left anterior cardinal 

 pronephric sinus 

 left duct of Cuvier 



renal sinus 



left posterior cardinol 



opening into atrium 



anterior hepatic vein 



posterior hepatic vein 

 ntestinal veins 



LAMPETRA 



B MYXINE 



Figure 11-7. Ventral views of the heart of the lamprey. A, with the several chambers exposed, 

 and of Myxine, B. (After Marinelli and Stronger, 1954, 1956) 



346 • THE CIRCULATORY SYSTEM 



