322 



L. V. HEILBRUNN. 



lower surface tension. Hence the concentration which resulted 

 was slightly under 0.17 per cent. In the table I have referred 

 to this solution as "0.16 per cent." As the figures show, it 

 proved highly effective. 



TABLE I. 



POLAR BODY FORMATION AFTER TREATMENT WITH SUBSTANCES WHICH LOWER 



SURFACE TENSION. 



All of the substances mentioned in the table produced a similar 

 morphological change in the egg. All of them caused the vitelline 

 membrane to become lifted away from the cytoplasm. The 

 details of this membrane elevation were watched in a great many 

 different experiments. The membrane first detached itself from 

 the egg at a number of points around the periphery. As a result 

 it appeared slightly thicker and for a minute or two it often 



1 This emulsion was made by stirring i c.c. ol toluol with 3 c.c. or sea water. 



2 Eggs were shaken while counting. As mentioned above this gives a higher 

 count. 



