GENERAL SUMMARY 57^ 



they are all Hymenomycetes which live on the fruit-bodies of other 

 Hymenomycetes or of certain Gastromycetes. While there are a 

 number of Ascomycetes which parasitise Basidiomycetes, there are no 

 ±{asidiomycetes which parasitise Ascomycetes. 



The author reviews our knowledge of the seven Hymenomycetes 

 which are known to be parasitic on other Hymenomycetes or on Gastro- 

 mycetes, and provides illustrations showing the connection of each 

 parasite with its host as follows : (1) Boletus parasiticus on Scleroderma 

 vulgare (2) Lepto7iia parasitica on Cantharellus cibarius, (3) Claudovus 

 subdepluens on Polyporus perennis, (4) Volvaria Loveiana on Clitocyhe 

 nebulans, (5) Nyctalis asterophora on Russula nigricans (6) Nvctalis 

 parasitica on Lactarius vellereus, and (7) Stropharia epimyces on Coprinus 



Boletus parasiticus may parasitise Scleroderma vulgare and this in 

 turn, may be a mycorrhizal parasite on the roots of an Oak tree 



Claudopus subdepluens found in the United States of America may 

 be Identical with Leptonia parasitica found in France. It is possible 

 that C. subdepluens lives a saprophytic existence on wood and is only 

 occasionally a parasite on Polyporus perennis. 



It is desirable that some one should attempt to produce fruit-bodies 

 ot Volvaria Loveiana by sowing spores of V. plumosa, which Quelet 

 and Maire regard as identical with V. Loveiana, on a healthy pileus of 

 Llitocybe nebularis. 



fyctalis asterophora, which parasitises species of Russula, Lactarius 

 and Collybia, reproduces itself normally by means of powdery stellate 

 chlamydospores which come into existence in its pileus-flesh. Its gills 

 are often either wanting or but very poorly developed and, when they 

 are comparatively well developed, they give rise to but few basidiospores 



In 1831, Krombholz sowed chlamydospores of Nyctalis asterophora 

 on the pileus of Russula adusta and obtained fruit-bodies of Nyctalis 

 asterophora within three weeks, thus proving that N. asterophora is a 

 Breiefd'^' ^^^^' *^'' ^^"^^^kable experiment was confirmed by 



The life-history of Nyctalis asterophora was carefully worked out by 

 Brefeld. From the details which he gives concerning the germination 

 of the spores and the structure of the mycelium, and from our modern 

 knowledge of sexual phenomena in the Hymenomycetes, we are justified 

 in concluding that N. asterophora is homothallic and that the chlamydo- 

 spores are produced only on a secondary mycelium. When N. asterophora 

 IS reproduced from generation to generation solely by chlamydospores 

 nuc ear association is not followed at any time by nuclear fusion and 

 nuclear reduction, so that normally this fungus is propagated in a 

 very different manner from that of most Hymenomycetes where nuclear 

 fusion and nuclear reduction take place in each basidium. 



The fruit-bodies of Nyctalis parasitica very rarely produce any 



