Experimental Studies on Germinal Localization. 47 



Fig. X. 



Development of Egg-fragments after vertical Section. 



75, y6, Equal twins, respectively in trefoil and polar lobe-formation; lobes 

 too small ; 77, 78, equal twins, nearly correct proportions ; 77a, 77b, typical trefoil 

 and 4-cell stages of one fragment; 78a, 78b ,typical 2-cell, slightly abnormal 

 4-cell stages of the twin fragment; 79, 80, twins, from a fertilized egg, 79, 

 nearly normal trefoil, 80, the twin, with reduced polar lobe; 81, 82, nearly 

 equal twins. 81, typical 4-cell stage, 82, its twin, nearly typical 2-cell stage; 

 83, 84, typical 4-cell and 8-cell stages, from upper pole, of the same fragment 



