Fig. 123. Development of the gobiid fish, Bathygobius soporator. (After Tavolga, '50, 

 slightly modified.) (A) Freshly stripped egg. Adherent filaments at proximal end of 

 chorion; micropyle at distal end. Peripheral cytoplasm partly concentrated at the pole of 

 the egg containing the female nucleus. (B) Fifteen minutes after fertilization; cyto- 

 plasm concentrating at nuclear pole of the egg; chorion expanding into shape of future 

 embryo. (C) Twenty minutes after fertilization; second polar body given off. (D) 

 Twenty-five minutes after fertilization. (E) Ninety minutes after fertilization. (F) 

 Seventeen hours after fertilization. (G) Twenty-four hours after fertilization. (H) 

 Thirty hours after fertilization. (I) Thirty-six hours after fertilization. (J) Ninety- 

 six hours after fertilization. (K) Ninety-six hours after fertilization. Hatching. (L) 

 Three days after hatching, temperature 27 to 29°. 



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