PLATE 7 



EXPLANATION OF FIGURES 



34 to 39 Ctenolahrus adspersus 9 X Fundulus heteroclitiis d'. 



34 A section through a polyspermic egg that cleaved at once into three cells. 

 The cleavage walls are not complete between the cells. Xo chromatin was found 

 on the spindle in the right-hand cell. 



35 The anaphase chromosomes from the central cell in figure 34. The spindle 

 was cut in four sections. Forty-two and forty-three elements are counted at the 

 upper and lower poles (in the figure), respectively. All chromosomes drawn. 



36 The anaphase chromosomes from the left-hand cell of figure 34. Not all 

 of the chromosomes could be shown in the drawing, although they are clearly 

 stained and well separated in the section. 



37 Telophase of the second cleavage. Some chromatin vesicles extend 

 toward the first-cleavage wall. The lagging is in the corresponding daughter 

 cells. Magnification not recorded. 



38, A and B Two sections of an early anaphase of the second cleavage. The 

 spindle is drawn out toward the cell wall which separates the two cells. All 

 of the chromosomes appear in the figures. 



39, A and B A sister cell to the one shown in figure 38. All of the chromosomes 

 are drawn. 



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