GERM CELLS IN PEDICELLLXA AMERICANA 51 



probably oogonial generation, where they are converted into 

 dumb-bell shaped rods. 



22. The egg nucleolus appears early during the oocytic 

 growth period and increases in size at the expense of the cleavage 

 products of the chromatin. 



23. It later becomes much vacuolated, stains throughout as 

 a plastin body, and with the approach of the first maturation 

 division disintegrates, its remains being cast out as a meta- 

 nucleolus (Hacker). 



Columbia University, Dept. of Zoology, 

 October, 1904. 



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