GAMBTOGENESIS OF SACCOCIRRUS 17 



(/) On Peri-nuclear Activity. 



In PI. 3, fig. 25, is drawn a yomig oocyte at a time when the 

 nucleolar deutoplasm is being foriiied ; this cell was prepared 

 by Da Fano's cobalt-nitnit e-formol-silver-nitrate method. It is 

 remarkable for the fact that it demonstrates very clearly the 

 extraordinary peri-nuclear activity at this stage of oogenesis. 

 It is possibly this material which stains basophil as described on 

 p. 16. In all my silver-nitrate preparations the oocyte at 

 this stage shows this peculiar appearance. 



The peri-nuclear cloud stains black or grey according as to 

 whether the preparation has or has not been toned, while the 

 nuclear reticulum and nucleolus are only faintly yellowish 

 and may subsequently be stained bright red in safranin. 



I look upon this cloud as the direct result of active protein 

 metabolism around the nucleus ; the protein is possibly forming 

 under stimuli sent forth from the nucleus. There is no evidence 

 that this cloud is chromatinic, for the Golgi silver-nitrate 

 methods (Golgi, Cajal, Da Fano) do not impregnate chromatin 

 in any cells I have studied. There is, in addition, no evidence 

 of intra-nuclear specks or dust as described by Schaxel for 

 Aricia foetid a. 



Later on this cloud disperses through the whole egg cyto- 

 plasm. 



7. Some Chromophility Eeactions of the Four Categories 

 OF Cytoplasmic Granules. 



The table given on p. 18 summarizes the differences which 

 can be shown to exist between the four categories of cyto- 

 plasmic granules found in the egg of Saccocirrus. Only those 

 methods which best show these differences are mentioned, 

 but besides I used many other fixing and staining techniques 

 (13). 



The nucleolar yolk-spheres or deutoplasmic elements 

 approach somewhat in their density to the mitochondria 

 and tend to stain rather hke them. Besides these methods 

 quoted there are such tests as the use of alcoholic or acidified 



NO. 261 



