284 BULLETIN No. 189 [June, 



to a fungus attacking crocus as TJianatophytum Crocorum. This ap- 

 pears, from his description and figures, to have been Rhizoctonia. A 

 new species of Rhizoctonia was described in France by Duby 20 as RJii- 

 zoctonia Allii on Allium ascalonicum. In 1843 Leveille 65 noted a simi- 

 lar Rhizoctonia on Rubia tinctorum, Solanum tuberosum, Phaseolus, 

 and Tulipa, without attempting to place it under any particular 

 species. In 1851 the Tulasne brothers 134 classified all the forms of 

 Rhizoctonia as a single species, Rliizoctonia violacea, a classification 

 which has been adopted by a number $>f writers. Rhizoctonia on cro- 

 cus was reported in Germany in 1858 by Kuhn. 64 He also found this 

 same fungus, which he identified as R. Medicaginis, on sugar beet. At 

 the same time he described a new species of Rhizoctonia on potato, 

 which he clearly distinguished from the above species and to which he 

 gave the name R. Solani. 



In the United States, Rhizoctonia was first reported by Webber 137 

 in 1890 on the roots of alfalfa in Nebraska. He listed the fungus as 

 Rliizoctonia Medicaginis DC. The first extended account of Rhizoc- 

 tonia in the United States was given by Pammel, 76 who found it caus- 

 ing a serious disease of beets in Iowa. Later, Atkinson 3 observed 

 Rhizoctonia causing damping-off of cotton seedlings, and following 

 that, of a number of other kinds of seedlings. In 1901 Duggar and 

 Stewart 32 added a large number of hosts subject to Rhizoctonia attack. 

 Many observations of other hosts and in new localities have since been 

 made until at the present time Rhizoctonia has been found on one or 

 more hosts in practically every state in this country. It has also been 

 reported from Canada, the West Indies, South America, India, and 

 Australia, so that it may be regarded as a truly cosmopolitan fungus. 



Duggar," in an article published since this manuscript was com- 

 pleted, brings out the fact that the violet root felt fungus, commonly 

 known in Europe and the United States as R. violacea, should be re- 

 ferred to as R. Crocorum (Pers.) DC. He states that unfortunately 

 this name has priority over the more descriptive name R. violacea. 

 Under R. Crocorum (Pers.) DC., Duggar lists the following pro- 

 visional synonymy: 



Tuber parasiticum Bull. (1791) 

 Sclerbtium Crocorum Pers. (1801) 

 Ehizoctonia Crocorum DC. (1815) 

 Ehizoctonia Medicaginis' DC. (1815) 

 Thanatophytum Crocorum Nees (1816) 

 Tuber Croci Duby (1830) 

 Ehizoctonia Eubice Dene. (1837) 

 Ehizoctonia Dauci Kabenh. (1859) 

 Ehizoctonia violacea Tul. (1862) 

 Ehizoctonia Asparagi Fckl. [non Fr.] (1869) 

 Hypochnus violaceus Eriks. (1513) 



"Duggar, B. M. : Ehizoctonia Crocorum (Pers.) DC. and E. Solani Kuhn 

 (Corticium vagum B. & C.) with Notes on Other Species. Ann. Mo. Bot. Gard., 

 2, 403-458, 9 figs., Sept., 1915. 



