Maturation of Parthcnogenetic and Sexual Eggs. 141 



phase instead of in an early anaphase. He never saw a telophase 

 stage and decided without any evidence that the chromosomes 

 never separated beyond the early anaphase stage and that later all 

 the chromosomes form the segmentation nucleus. 



This is probably not the case because one polar body can always 

 be seen near the periphery of the egg after the first cleavage, in 

 total mounts prepared by the method already described. Some- 

 times a constriction can be seen across the middle of the polar 

 body giving it the appearance of being divided into two parts. 

 In the two-cell stage of the egg after the two blastomeres separate 

 the polar body is always found in the space between the two cells 

 (Fig. 2, A-B). In the four-cell stage it is seen at the point of junc- 

 ture of the four cells (Fig. 2, C). 



Fig. 2 Female parthenogenetic egg. A, B, eggs in the two-cell stage, showing one polar body; 

 C, egg in the four-cell stage, showing one polar body at the intersection of the two cleavage planes. 



IV MALE EGG 



The male egg is much smaller than the other two kinds of eggs 

 and has a thin envelope around it similar to that of the female 

 parthenogenetic egg. The maturation spindle was seen several 

 times when the chromosomes were in metaphase, anaphase and 

 telophase stages. In two cases of telophase ten and fourteen 

 chromosomes respectively were counted on one end of the spindle 

 (Fig. 3, C-D). Polar views of the metaphase stage showed clearly 

 eleven to thirteen chromosomes (Fig. 3, A-B). They were always 

 less in number and larger in size than the chromosomes in the 

 metaphase stage of the female parthenogenetic eggs. 



