MORPHOLOGY AND PHYSIOLOGY OF GENUS URONYCHIA 389 



the basal bodies. Simply cutting the cirri without injuring the 

 basal bodies does not result in regeneration. 



8. Abnormalities may be produced in Uronychia if the micro- 

 nucleus is injured. Such forms die without dividing, 



9. There is evidently a division plane established at a fairly 

 early period in the cell, and this is not altered by cutting the cell. 



LITERATURE CITED 



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