OMPHALIA FLAVIDA 



405 



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extending from the centre almost to the margin of the colony. 

 After twelve days a few much larger bodies, having deep-yellow 

 hemispherical heads, began to push up from 

 the centre, and in fifteen days some of them 

 had become perfect Omphalia flavida agarics 

 of a light sulphur colour, with erect slender 

 minutely hirsute stipes and membranous sub- 

 hemispheric or broadly conical pilei (Fig. 203). 

 As inocula for further subcultures on sterilised 

 bread, Ashby used either (1) s^iZ6wm-heads or 

 (2) fragments of the stipes or pilei of the 

 agarics, with the result that the mycelium 

 always gave rise to both sh76wr?i-bodies and 

 Omphalia fruit-bodies. Basidiospores, ob- 

 tained from the gills of one of the agarics, 

 were sown ; and the mycelium, after being 

 transferred to a corn-meal agar sloj)e, yielded 

 many 5^i/6wm-bodies and a few perfect 

 agarics. Thus Ashby conclusively proved 

 that the mycelium of Omphalia flavida 

 produces fruiting structures of two kinds : 

 (1) ordinary hymenomycetous sporophores 

 which liberate basidiospores, and (2) peculiar 

 pin-shaped stilbum-hodies which are sporeless 

 but each of which readily sets free its stilbum- 

 head. 



In the autumn of 1925, Mr. Ashby, at the 

 Imperial Mycological Institute, Kew, kindly 

 showed me his cultures of Omphalia flavida 

 and gave me a subculture. I took this to 

 Winnipeg and, in conjunction with T. C. 

 Vanterpool, repeated some of Ashby's experi- 

 ments. The mycelium was transferred to 



Fig. 204. — Omphalia fi avid a, growing on an oat-meal agar 

 slope in a test-tube. The mycelium has produced 

 numerous gemmifers and a few perfect fruit-bodies. 

 Culture several weeks old. Natural size. 



