282 



Mycologia 



that after the anastomosis of two hyphal cells of different thalli, 

 the primary mycelium takes on the characteristic of the second- 

 ary one. Through this anastomosis (plasmogamy) of cells the 

 cytoplasm as well as the nucleus or nuclei of one cell may pass 

 into the other. The fusion of two cells with more than two nuclei 

 generally results in the disintegration of the superfluous ones. 

 Unfortunately, the cytological evidence offered for this most in- 

 teresting claim is altogether insufficient and the figures are quite 

 inadequate. 



The most aberrant feature in the author's results is the claim 

 that the nuclei of the early germ tube divide amitotically. Here 

 again the evidence does not appear to be satisfactory. Two 

 nuclei lying close together with imperfectly stained nuclear mem- 

 branes do not indicate all the conclusions that the author sug- 

 gests ; nor in m}^ opinion do dark or heavily stained protoplasmic 

 strands between two nuclei suggests anything more than imper- 

 fect staining. It seems that Flemming's Strong Solution destroys 

 the delicate spindle fibers in the fungi. The claim that in young 

 hyphae the nuclei rarely ever show chromatin seems to be a retro- 

 gressive step in the cytology of the fungi. A number of students 

 of the Ascomycetes, as well as the Basidiomycetes have shown 

 rather clearly that the nuclei of the hyphae in these fungi are 

 quite like those of higher plants. 



As noted, Miss Bensaude's account of conjugate nuclear divi- 

 sion and the formation of clamp connections agrees with that of 

 Kniep. The nuclear division is, as a rule, preceded by the for- 

 mation of a protuberance in the middle of the cell which is to de- 

 velop into a clamp. The nuclei migrate into the region of the cell 

 where this protuberance is formed. One of the nuclei which 

 Miss Bensaude now calls plus enters this rudimentary clamp and 

 the other minus remains in the hyphal cell. Spindles are formed 

 lying parallel to each other and the nuclei divide. One of the 

 plus daughter nuclei passes back into the mother cell and the 

 other goes to the tip of the little beak. One of the minus 

 daughter nuclei goes to the apical portion of the mother cell, the 

 other to the basal part. Two contiguous cross walls are formed, 

 one at the base of the young clamp and the other in the mother 



