1/6 GRACE MEDES. 



fibers lie like a few strands obliquely through the cytoplasm 

 (Fig. 25, ct seg.}. As soon as the chromosomes reach their 

 destination at the extremity of the spindle, the net-work of the 

 cell commences to re-form, and, within a remarkably short period, 

 all trace of division is lost from the cytoplasm. 



Soon after the second division occurs, the centrosomes also 

 disappear. In the case of the former division, it was stated that 

 they either lost their staining capacity or became indistinguishable 

 from the remains of the karyosphere massed in their vicinity. 

 But in this instance, the former is shown conclusively to be the 

 case, partly because of the fact that here there are no such gran- 

 ules with which they could become confused, and partly for the 

 reason that for a considerable time the aster remains visible, 

 although at the. point from which the fibers radiate, no centrosome 

 is to be seen (Figs. 25, 26). 



I wish to express my gratitude to Dr. C. E. McClung under 

 whose direction the work was done, and to Mr. M. W. Black- 

 man, for assistance in supplying material and for many valuable 

 suggestions. 



LABORATORY OF ZOOLOGY, UNIVERSITY OF KANSAS, 

 June 8, 1904. 



BIBLIOGRAPHY. 

 Blackman, M. W. 



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