208 



BRANCH CHORDATA 



SUB-CLASS III. DIP'NOI 



The "lung fishes" are snake-like or eel-like (Fig. 168), and 

 bear small, soft, cycloid scales, small paired fins, and a diphycer- 



Fig. 168. Lung fish (Protop'terus annecleris). (Boas.) 



Fig. 169. The Cer'alodus of Queensland, an air-breathing and water- 

 breathing mudfish of the ancient type, with paddle fins. (From Baskett, 

 " The Story of the Fishes," D. Appleton and Co., Publishers.) 



cal caudal fin. The skeleton is largely cartilage and the noto- 

 chord persistent. They live in fresh water, and usually breathe 



