390 MONTGOMERY. [Vol. XV. 



Wager ('93), nuclear division in Hyvienoniycctcs agaricus : 

 each nucleus of a basidium contains one large nucleolus, besides 

 the nuclear network. The two nuclei of the basidium fuse 

 together and form one nucleus, in which afterwards the two 

 nucleoli later fuse to form one nucleolus. This latter is 

 often vesicular in structure. In the mitosis it lies close to the 

 nuclear membrane, it gradually loses its staining intensity, 

 decreases in size, and finally disappears; at the same time the 

 cytoplasm in its neighborhood stains more deeply. But some- 

 times it persists until the diaster stage. " From the fact that 

 the chromosomes begin to stain red at the time of the disappear- 

 ance of the nucleoli, it would further appear that the former 

 can take up nucleolar substance from the nuclear sap, and as 

 fast as the nucleoli disappear the chromatic elements become 

 more deeply stained red." In A. stcrcorai'iiis, in the daughter- 

 nucleus, " the chromatin mass appears to be transformed at 

 once into the nucleolus," and only later a chromatin network 

 appears. " I would suggest that the nuclear threads take up 

 the dissolved nucleolar substance at some period during the 

 •division, and carry it over into the daughter-nuclei, to be given 

 up again later as the nucleoli of the latter. , . . But a certain 

 quantity of the dissolved nucleolar substance probably escapes 

 into the cytoplasm when the nuclear membrane disappears, and 

 this would be taken up at a later stage into the daughter-nuclei, 

 as is shown by the increase in size of the nucleoli, and by the 

 •decrease in the capacity of the protoplasm for taking up stains." 



Zacharias ('93) finds in plants that the nucleolus and cyto- 

 plasm are erythrophilic, the nuclein (chromatin) network is 

 cyanophilic. 



Belajeff ('94), " PoUenmutterzellen " of Larix : after the 

 disappearance of the nuclear membrane in mitosis the nucleolus 

 becomes gradually smaller and then disappears ; several nucleoli 

 reappear within each of the daughter-nuclei. *• Es ist zu 

 bemerken, dass nach der Auflosung der Nucleolen der Mutter- 

 zelle im Zellplasma eine gewisse Anzahl grober Kornchen 

 erscheint, welche mit Safranin farbbar sind. Mit dem Beginn 

 der Nucleolenbildung in den Tochterzellen verschwinden die 

 Kornchen vollkommen. . . . Ich erklarte mir die Ergebnisse 



