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Harry Lewis Wieman. 



deeply staining cytoplasm the evidence of a secretory function 

 that is entirely absent in the epithelial cells. This view of the ori- 

 gin of the follicles is different from that prevailing in the literature, 

 but I am inclined to believe that a similar method of follicle for- 

 mation may be found to be of much wider occurrence in other 

 species of insects than is at present supposed. 





Fig. X. Photograph of a longitudinal section of a half-mature ovum showing 

 the form of the nutritive stream, n, nucleus; n. s., nutritive stream. 



The red granules appearing with the beginning of the growth 

 period, enter the egg by way of the egg string, and are at first 

 evenly distributed throughout the cytoplasm. As the egg string 

 increases in size, the granules are supplied in larger amounts 

 than can be disposed of, and the result is an accumulation of 



