434 EMBRYOLOGY OF THE LOWER VERTEBRATES CH. 



Fia. 200. Stages in the development of Lepidosiren 



\. stage 23; B, 25; C, 26; D, 28; B, 31; F, 33; G, 35; 

 H, 86. c.o, cement organ ; E, eye ; e.g, external gill ; M, 

 month; p.f, pectoral fin; pl.f, pelvic tin : >/../-, spiral valv.- of 

 intestine. (A - F x 3 ; G x 2-5 ; Hx2.) 



c.a 



*9 



