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WILLIAM B. KIRKHAM. 



egg are drawn into the equator of a new spindle, split longitudi- 

 nally, and the twenty-four daughter, univalent chromosomes 



FIG. 3. Ovarian egg showing first polar body and second polar spindle. Seven- 

 teen masses of chromatih, some of which are undivided dyads, are scattered through 

 the first polar body ; twenty-four univalent chromosomes appear in the equator of the 

 second polar spindle. Certain chromosomes have been added from adjacent sections. 

 A minute centriole appears at each pole of the second spindle. The zona pellucida 

 is represented by a double line. ( 1200. 



FIG. 4. Diagram of univalent chromosomes in second polar spindle, indicating 

 difference in size. 



lengthen out into filaments of various sizes (Fig. 4). Like the 

 first polar spindle the second varies in size, and lies with its axis at 



