SCLEROTINIA. 265 



(Peziza Kmiffmaniana Tichom.)^ as related to, or identical with 

 Sd. sderotiorum. Behrens, however, is inclined to ascribe it 

 to Sd. Fuckeliana, which has occasionally a Botryiis-stnge. This 

 hemp disease has also been found in Alsace.^ 



Humphrey ^ regards this species as the cause of a disease 

 of indoor cucumbers ; he ascribes a Botri/tis-stage to it. 



Sd. sderotiorum is best known by the conical funnel-shaped 

 depression in the hymenial disc, not present in other species. 



Sclerotinia trifoliorum Eriks * (U.S. America).^ Clover 

 is not attacked by the Sderotinia last considered, but falls an 

 easy prey to this species, which again derives but scanty nourish- 

 ment from such food as fresh carrots. Sd. trifoliorum is 

 observed wild only on species of clover, and is there fairly 

 common ; many other plants, however, have been artificially 

 infected by it. Host-plants are attacked through their green 

 foliage, which very soon becomes brown and shrivels up. If 

 the atmosphere be sufficiently moist, the mycelium emerges 

 on the exterior and spreads to neighbouring organs or plants. 

 Sclerotia are not often formed superficially as with Sd. 

 sderotiorum, because the mycelium lives principally inside 

 the plant tissues. This mycelium resembles that of Sd. 

 sderotioriim in its peculiar property, that successful infection 

 only follows if the fungus has lived for a time saprophy tically ; 

 on this account direct infection by spores is ■ harmless. In the 

 secretion of an enzyme and of oxalic acid, and in the manner 

 in which it destroys the tissues of its host-plant, this species 

 behaves like Sd. sderotiorum just described. It is distinguished 

 by its larger ascospores, and the absence of a central funnel- 

 shaped depression in the hymenium. Spores germinated in water 

 produce numerous bodies (so-called spermatia) which distinguish 

 the species from Sd. Fuckeliana where this does not take place. 



Eostrup^ found in Denmark that Medicago lupulina suffered 



^Tichomiroff, Bull. soc. nat. de Moscou, 1868. 



^ Behrens, ' ' TJeber das Auf treten d. Hanf krebses im Elsass. " Zeitschrift f. 

 Pflamenhranlcheiten, 1891, p. 208 ; " Trockene u. nasse Faule d. Tabaks," idem, 

 1893, p. 82. 



'Humphrey, Agric. exper. station Mass., 1892, pp. 212-224. 



^Ktihn, "Die Sklerotienkrankheiten d. lOees." Hedwigia, 1870. 

 Rehm. , Entwickelurtysgesch. eines d. Khe zerstm'enden Pilzes. 



^ Massee (British Fungus-Jlora, IV., 1895). "There is no evidence of this species 

 having occurred in Britain. " 



^Kostrup, Tidssh-ift for Landohonomie, 1890. 



