BROODSTOCK, SPAWNING, AND EGG HANDLING 177 



THICKENED EDGE OF BLASTODERM 



EMBRYO 



D. SIX DAYS AFTER FERTILIZATION, 51.5°F AVERAGE TEMPERATURE 

 (117.0 T.U.). 



EDGE OF BLASTODERM 



EMBRYO 



E. SEVEN DAYS AFTER FERTILIZATION, 51.2°F AVERAGE TEMPERATURE 

 (134.4 T.U.). 



LIP OF BLASTOPORE 



F. EIGHT DAYS AFTER FERTILIZATION, 51.7°F AVERAGE TEMPERATURE 

 (157.5 T.U.). 



Figure 61. Continued. 



