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•JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 



the lower half darker. The contents of the perithecia consist of long, 

 cylindrical, transparent cells, or asci, each of which encloses eight dark- 

 brown sporidia, of an almond shape (40-50 fx long). 



It is not unusual to meet with these sclerotia in mushroom beds 

 occasionally producing these stems, and sometimes only the thickened, club- 



Ftg. 189. — Xylaria vaporaria. (Gardeners' Chronicle.) 



a, complete plant; B, one of the fruit-bearing teiruinals; c, section of same 

 showing perithecia ; n, ascus with sporidia ; e, young ascus ; f, paraphyses. 



like sterile heads, they seldom being allowed to remain until the receptacles 

 are fully developed. 



Of course such beds have to be destroyed at once and the house 

 disinfected before any attempt is made to grow mushrooms on the spot. 



Sacc. Syll. i. 1292 ; Curr. Linn. Trans, xxiv. t. 625, f. 17, 26; Cooke, 

 Hdbk. No. 2378 ; Gard. Chron. Dec. 20, 1879, p. 801, fig. 132. 



