468 WESLEY R. COE, 



their fibres reach far beyond the bases of the degenerating fibres of 

 the old cleavage-asters. They increase further in size and form the 

 second cleavage-spindle as usually described. Their centrosomes have 

 remained nearly constant in size. 



One of the most remarkable features of these eggs is the great 

 persistence of the degenerating aster-fibres, in the inner aster of the 

 second polar spindle, in the sperm-asters, and in the cleavage-asters. 



Sheffield Biological Laboratory 

 of Yale University, June 1st 1898. 



Literature. 



1. Andkews, E. a., Some activities of polar bodies, in: Ann. Mag. 

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2. BovERi, Th., Ueber das Verhalten der Centrosomen bei der Be- 

 fruchtung des Seeigeleies etc., in : Verh. phys.-med. Ges. Würzburg, 

 V. 29, 1895. 



3. — Ueber das Verhalten der chromatischen Kernsubstanz bei der 

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4. Caknoy, J, B., et Lebrun , La fécondation chez l' Ascaris megalo- 

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5. v. Eklanger, R., Beiträge zur Kenntniss der Structur des Proto- 

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8. Hacker, V., Ueber den heutigen Stand der Centrosomenfrage, in: 

 Verh. Deutsch, zool. Ges., 1894. 



