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the vegetative liypliae. They are here much larger than in P. li- 

 miseda (fig. 1, 13 and 20, 21), but their quantity is considerably 

 less than in the latter species. In young ascogonia the immber of 

 nuclei does not exceed two or three (fig. 20j. The number of nuclei 

 in more mature stages distinctly increases ffig. 22, 23). We can 

 notice here, as well as in P. fimiseda, the beginning of the diffe- 

 rence in their dimensions (fig. 21, 23). This difference is seen not 

 only in the cells of more or less developed perithecium (fig. 23), 

 but even when the ascogonium is as yet only covered by one layer 

 of interlacing covering hyphae (fig. 21). 



The nuclei are gathered in groups, or lie without any fixed 

 order, but at the same time, in distinction from the P. fimiseda, 

 there are always cells in which the nuclei are placed in pairs 

 (fig. 22, 23, 24). This fact which attracted attention was, certainly, 

 not accidental. They are not fusing nuclei, for their contours are 

 sharply outlined. Further Ave can scarcely see in this, the same 

 phenomena which one observes, for instance, in Pyronema (Clausseni, 

 where the nuclei in the ascogonium are only placed in it by pairs, 

 Avithout fusing, to pass afterwards together into the ascogenous 

 hyphae. The nuclei in the Podospora, by the time of the appea- 

 jfance of ascogenous outgrowths, lie in the cells of the ascogonium, 

 usually quite separately (fig. 25) and only in the ascogenous hyphae 

 Ave can perceive them again lying in pairs. 3Iost probably tlie 

 pairing of the nuclei, one observes in the ascogonium, which has 

 not yet produced ascogenous threads, can be explained as resulting 

 from their dividing in two. And in fact the karyokinesis can be here 

 obserA'ed. On the fig. 26 you can see the nuclei division in the 

 4-ells of the ascogonium. Although the stage of development of 

 the fruit body is advanced, the ascogenous hyphae do not yet 

 appear. We may notice, that a whole row of nuclei divides fon 

 the drawing is only shown part of it), but it is necessary to say, 

 that such simultaneous division does not, perhaps, usually take 

 place, and in this case its presence can be explained by the fact, 

 that the development of the perithecia did not proceed in quite an 

 usual manner. It was, for a time artificially retarded, after which 

 it proceeded with an accelerated pace. To obtain this result tlie 

 cultures of the fungus which began fruiting, were placed for twenty 

 four hours in a cold cupboard with 3" to 5" С temperature, and 



