624 



Comparative Morphology of Chordates 



Fig. 476. Diagrams of heart and aortic arches in (A) an amphibian, (B) a 

 mammal, (C) reptiles— Chelonia, Lacertilia, Ophidia, Rhynchocephalia, and 

 H a . crocodlIe - Ventral view of heart represented as untwisted so as to bring 

 chambers into a single plane, with venous sinus behind and ventricle in front 

 (b) Transverse section of region of bulbus cordis; (t) transverse section of region 

 of truncus arteriosus. [Author's note: The correctness of Goodrich's representation 



