J. R. GREGG 



233 



Stage Numbeir 



6 



Age: in Hours at 18° Centigrade 



96 



Length in Millimeters 



4 



MUSCULAR RESPONSE. 



9 



16 



HEART BEAT 



20 



140 



gill circulation 



MATCHING 



21 



I6E 



MOUTH OPEN 



CORNE.A TRANSPARENT 



22 



192 



6 



TAIL FIN CIRCULATION 



Fig. 1. {Continued.) 



