CHAPTER IV 



THE SYNCHYTRIAN NUCLEUS 



SOME protists have two modes of reproduction, firstly by 

 mitotic cell-division, and secondly by the way of a generative 

 chromidium, see Figs. 1 and 2. Both these modes are 

 found in the genus Synchytrium. 



A great variety of nuclear processes has already been 

 made known by different observers, and the bearing these 

 have on general cytology and pathology makes their close 

 study necessary. 



F. L. and A. C. Stevens commented on the work of 

 Dangeard and of Rosen on 8. Taraxaci in a note to the 

 effect that current theories of the nucleus would suffer 

 violence if the conditions reported by these authors really 

 existed. Dangeard had described as an occasional occur- 

 rence a direct division of the nucleus by inflexion of the 

 nuclear membrane. Rosen found that in the primary 

 nucleus the chromatin forms a spireme, and the nucleolus 

 divides, the halves migrating to form daughter nuclei, 

 thus completing a nuclear division in the spireme condition 

 without the aid of the usual achromatic structures. The 

 subsequent successive divisions Rosen found to assume more 

 and more the character of an ordinary mitosis. The Stevenses 



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