﻿A B 



Fig. 1. — Dorsal view of Lungs of Polypterus (A) and Lcpidosiren (B). 

 (In A the riglit lung and intestine have been slightly displaced: the 

 symmetrical arrangement alluded to in the text is consequently obscured.) 

 m^. , intestine ; left lung ; 7. left pulmonary artery ; oes., oesophagus ; 

 lih. , pharjaix ; r.l., right lung ; r.-p.a., right pulmonary artery ; st., stomach ; 

 XI. , left vagus ; Xr. , right vagus. 



