102 Eei'ORT of the Botanist of thb 



described were not to be regarded as distinct, and all were thrown 

 together under the name RMzoctonia vlolacea. In 1858 Kilhn^ 

 discussed more at length certain forme of economic importance, 

 and made known some new hosts among agricultural plants. 

 FuckeP reported a perithecial form, Leptosplimria {Bijssotheckim) 

 circina'Tis and also a pycnidial form of R. medicaginis D. C. The 

 only claim for the relationship of these forms was based upon 

 their association in nature. 



In a similar way other fungi have been subsequently suggested 

 as perfect stages of Rliizoctonia, but evidence of genetic relation- 

 ship is constantly lacking. 



Among forms more recently described may be mentioned an 

 oak root-fungus discovered by Hartig.^ It was found closely 

 associated with the ascomycetous form RosselUnia qiiercina, so' 

 that the reported rhizoctonial stage was described under the 

 latter name. 



Scholtz* has described RMzoctonia strohi, can'sing a disease of 

 the Weymouth pine, and he was unable to establish any con- 

 nection between the hypha3 of this RMzoctonia and those of cer- 

 tain fruiting forms on plants killed by this disease. 



Frank^ has recently reported R. violacea as destructive to grape 

 vines. A perfect form is reported which he names Thclephora 

 rMzoctonicB. 



Rostrup has also described RMzoctonia fusca, the cause of a 

 disease of turnips in Sweden. Comes, Sorauer and Frank have 

 also given full general accounts of the European rhizoctonial 

 diseases in their works on plant dseases. 



The list of European host plants now covers a very wide 

 range. The following are the most important plants affected: 

 alfalfa, asparagus, beet, carrot, various clovers, crocus, fennel, 



* Kiihn, J. — Krankheiten der Kulturgewachse, Berlin, 1858. 



* Fuckel.— Botan. Zeitung, 34, 1861 (p. 250).. 



* Hai'tig, R. — Untersuch. aus d. forstbotan. Institut zu Miinchen, 1888. 



* Scholtz. — RMzoctonia stroM, ein neuer Parasit der Weymoutliskiefer. 

 Verhandl. d. zoolog. botan. Ges. Wien, 47:541-557, 1897. 



'Frank, B. — Bin neuer Rebensehiidiger in Rheinhessen [Ref. Centrbl. t 

 Bakt. Parasitenk. u. Infektionskr., 4, 781, Abth. II.] 



