412 GEORGE T. HARGITT 
reticulum. The first maturation spindle is formed outside the 
membrane of the germinal vesicle, the membrane breaks and the 
chromosomes enter the spindle. 
Not all the chromatin of the germinal vesicle enters into the 
formation of the chromosomes, but the apparently larger amount 
escapes into the cytoplasm when the membrane of the germinal 
vesicle breaks. The chromatin which escapes is of the same sort 
and has the same history as the chromatin granules which form the 
chromosomes. This is evidence against a continuity of chromatic 
material from generation to generation. 
There are ten chromosomes in the maturation spindle, the 
reduction apparently having taken place at the time of the polar 
arrangement of the chromatin loops in the primitive egg cell. 
Two polar bodies are formed. 
On account of the evidence against the continuity of chromatic 
matter from one generation to another, and because there is shown 
to be no difference between the germ plasm and the body plasm 
until after the egg has begun to grow, it is suggested that we must 
come to look to the ultimate chemical composition and constitu- 
tion for explaining cellular activities and relations. 
January 15, 1913. 
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duen der Hydropolypen. Zeitschr. f. wiss. Zool., Bd. 87, pp. 1-335, 18 pl. 
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