STUDIES OF AMITOSIS 499 



by application of a 5 per cent solution of ether in water. He, 

 however, doubted if such amitotic phenomenon really correspond 

 to the normal amitosis, and proposed to call the former process 

 ' pseudoamitosis. ' 



His ('00) states that the nuclear division by constriction, 

 without any preparatory change in the nucleus does not occur 

 in the periblast of fish, and he considered the so-called amitosis 

 demonstrated in this tissue as a peculiar form of multipolar 

 mitosis. 



Magnus ('00) showed that in the case of certain cells of in- 

 fected roots of Listera and Orchis, there is a kind of fragmenta- 

 tion of nucleus, which is not a dying condition but a special 

 adaptation in the nuclear activity. 



Nathanson ('00) believed in the external influence upon the 

 method of cell division, when he experimented with Spiragyra, 

 Closterium, and some higher plants. He claims that it is the 

 action of ether that determines amitosis. 



Regaud ('00) observed in the case of rats that the nuclei of 

 Sertoli's cells and spermatogonia divide amitotically, but the 

 stock of cells ultimately producing spermatozoa divide by mito- 

 sis later, so he maintained that amitosis, which is in most cases a 

 manifestation of cellular degeneration, is not always a sign of 

 fatal degeneration of the cell. 



Wilson ('00) in his review of the subject, says that amitosis in 

 the vast majority of cases, is a secondary process which does 

 not fall in the generative series of cell-division, and regards 

 Flemming's hypothesis as, in a general way, representing the 

 truth. 



Gross ('01), working on ovaries of thirteen species of Hemip- 

 tera, supported Ziegler's theory by showing that the cell which 

 has undergone amitosis does not belong to the generative cycle 

 of true germ cells. He also pointed out that there can be dis- 

 tinguished two kinds of amitosis — the degenerative and secre- 

 tory amitosis. 



Caminiti ('03), studying amitosis in certain liver cells, states 

 that normally amitosis may exist as an equally important proc- 

 ess of cell multiplication as mitosis. 



