CHIM^ROID FISHES AND THEIR DEVELOPMENT. 



cc 



DD 



be. Body cavity. 

 (/' . .</" Evagination of gut wall to form the 



first and second sill openings. 

 />. Heart. 



Figs. 73 T-EE Continued. 



nc. Neural crest, 

 in. Subnotochordal rod. 

 y. Yolk lying free in cavity of gut. 



