408 SUMMARY OF CURRENT RESEARCHES RELATING TO 



Cytology of Hymenomycetes.* — Michael Levine gives a history of 

 the cytological work done on these fungi. He germinated spores of 

 Pholiota prsecox and records the phenomena connected with the nuclei 

 in the vegetative cells, but his chief observations were made on Bo let L 

 He was not able to induce germination in the spores of the latter. 

 Levine sums up his results thus : — 



1. Spores of Pholiota prsecox produced multinucleate germ-tul)es ; 

 after forty-eight hours the mycelium still consisted of long multinucleate 

 cells. After three days, uninucleate and binucleate cells were present. 



2. The mycelia of several other Agarics and Polypores consisted of 

 binucleate cells. 



3. The cells of the mature stipe of Boletus grcmulatus are all 

 multinucleate, the cells of the ring binucleate ; the cells of the flesh 

 and trama are Innucleate. The subhymenial cells of all the Boleti 

 examined were binucleate. 



4. The cystidia of Boleti occur variously, they are binucleate and 

 appear to be glandular in their functions. 



The nuclear phenomena in the Imsidium are typical in all the species 

 of Boletus examined. Fusion of the two primary nuclei of the basi- 

 dium was observed in several. 



The chromosome number in the first division was six to eight. In 

 the second division the number was not determined, but it was always 

 more than two. At the end of the second division the centrosomes 

 become attached to the walls of the basidium and form the points of 

 origin of the sterigmata. They are carried up with the growth of the 

 sterigmata and draw the nuclei into the spores. The spores are uninu- 

 cleate at first Ijut the primary spore-nucleus divides at once. 



Finally, he concludes that an alternation of generations comparable 

 to that in the Uredineae is also present in the Basidiomycetes. The 

 sporophyte begins at some indefinite point in the mycelium and extends 

 through the development of the carpophore. 



Observations on Polyporus squamosus.f — Reginald Price has 

 made a series of spore cultures and inoculations of this fungus. Steri- 

 lized blocks of wood were used in plugged test-tubes, but the mycelium 

 was not visil)le until about two months after sowing the spores. Cul- 

 tures were also made on various blocks of wood, and ultimately somewhat 

 peculiar sterile fructifications were formed. Spores were also germinated 

 in hanging-drops, and inoculations were made on trees. Old wound 

 surfaces and dead twigs were readily attacked ; the living wood was 

 less easily infected. 



Wood-destroying" Fungus. J — Adeline Ames describes a new fungus, 

 Porla atrosporia. The wood on which the fungus grew, partly Taxodium 

 disticlmm and partly Piiius palustris^ was very badly rotted. The 

 fungus is distinguished by the dark-coloured spores. Attempts to 

 make cultures and thus to follow the action on the wood failed. 



* Bull. Torrey Bot. Club, xl. (1914) pp. 137-81 (5 pis.). 

 t Proc. Cambridge Phil. Soc, xvii. (1913) pp. 168-9. 

 J Bot. Gaz., Iv. (1913) pp. 397-9 (6 figs.). 



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