Parker and Davis. — Heart blood vessels in tisbes. 
PLATE 3. 
Fig. 7. Dorsal view of the heart and its superficial veins in Carcliarias. The 
venous sinus is laid open. 
Fig. 8. Dorsal view of the heart and its superficial veins in Raja. The venous 
sinus is laid open and the auricle removed. 
Fig. 9. Dorsal view of the heart and its superficial veins in Anna. The venous 
sinus is laid open. 
Fig. 10. Ventral view of the heart and its superficial veins in Carcharias. 
Fig. 11. Ventral view of the heart and its superficial veins in Raja. 
Fig. 12. Ventral view of the heart and its superficial veins in Amia, 
