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THE AMEBIC AX NATUBALISI [Vol. XLIV 



clearer, as I have elsewhere pointed out. The continuous 

 plasma membrane enclosing a coenocyte is plainly in its 

 relation to the other cell contents to be compared with 

 the same structure in an uninucleated cell rather than with 

 the aggregate of membranes which bound off a mass of 

 tissue from its environment and the cells of the tissue 

 from each other. 



It is further most interesting to note that De Bary's 

 conception of the male element in the oomycetes as gono- 

 plasm, a mere unbounded portion of the contents of the 

 antheridium, has been entirely confirmed by subsequent 

 cytological research, and it is further proof of the super- 

 ior significance of the nucleus as the carrier of the idio- 

 plasm in sexual fusions that in such forms as Cystopus 

 canflifhts. for example, it is merely one of the several 

 nuclei in the antheridium, and that with no definitely 

 limited cytoplasmic unit which migrates through the 

 conjugation tube and fertilizes the egg. The differentia- 

 tion of the male gamete is not here an ordinary process 

 of cell division, but a mere flowing out of one of the 

 nuclei of the coenocytic antheridium. 



The most striking discovery as to fusion in the fungi 



of the more important later results was the observation 

 bv Wager of paired nuclei and the subsequent fusion of 

 these nuclei in the young basidium. 



Wager was mistaken in describing a series of such 

 fusions by pairs, but the clear account of the nuclear 

 structures which he gave and the evidence that nuclear 

 division occurs by a karyokinesis like that of other plants 

 and animals showed for the first time the possibility of 

 determining the nature of the various reproductive bodies 

 in fungi by a more exact cvtological investigation of them 

 than had before been thought possible. 



Wager brought the first proof of the existence of an 



