GAMETOGENESIS OF SACCOCIRRUS 13 



With almost a suddenness a large number of nucleolar yolk- 

 bodies appear in a ring surrounding, but some distance away 

 from, the nucleus (PI. 4, fig. 34, is a somewhat later stage). 



The appearance of this ring of numerous nucleolar yolk- 

 bodies corresponds more or less closely with the spreading out 

 of the basophil peri-nuclear cloud referred to below (p. 17). 



The next period sees the complete change of the cell from 

 primary oxyphilia to a temporary basophilia : this activity 

 is often shown plainly with the Mann-Kopsch osmium tetroxide 

 method, of which PI. 4, fig. 29, is an example ; the whole 

 appearance of the cell seems to change. Later the peri-nuclear 

 vacuoles disappear, the cytoplasm becomes smooth, and the 

 nucleolar yolk-bodies are the most noticeable element in the egg. 



In PI. 4, fig. 30, is an egg fixed for six weeks in formol- 

 Flemming ; the true yolk (derived I believe from the Golgi 

 elements) has gone black with the osmic acid, while the 

 nucleolar yolk-spheres are pale, in this case fuchsinophile, 

 bodies ; neither mitochondria nor Golgi elements appear in 

 this preparation. 



That the nucleolar deutoplasm or yolk-spheres go on dividing 

 in the egg cytoplasm seems to me a very likely suggestion, 

 but I was unable to prove that such was the case. How 

 then otherwise can we account for the extraordinarily rapid 

 increase of clouds of these alizarin-staining granules such as 

 appear in PI. 4, fig. 34 ? It seems certain that smaller nucleoli 

 inside the nucleolus keep budding off extra-nuclear fragments 

 (PI. 4, fig. 34), but this would not account for the arrangement 

 and rapid growth of clouds of granules such as those at nl in 

 PI. 4, fig. 34. 



In PI. 4, fig. 30, which was drawn from a very clear example 

 where the nucleolar yolk-spheres were large, I could not see 

 any of the latter undergoing binary fission ; 1 am therefore 

 disposed to believe that these cytoplasmic nucleoli bud off 

 little pieces just as the larger nucleolus is doing in the cell 

 drawn in PI. 4, fig. 34 ; and then these little pieces themselves 

 grow larger. 



In PI. 4, fig. 31, is a part of the cytoplasm of a nearly ripe 



