444 FUNGOUS DISEASES OF PLANTS 



IV. A ROOT AND STEM ROT FUNGUS 

 Cortidum vagum B. & C., var. Solani Burt. 



ATKINSON, GEO. F. Some Diseases of Cotton. Ala. Agl. Exp. Sta. Built. 41 : 



30-39. 1892. 

 CLINTON, G. P. Rhizoctonia (Rosette). Conn. Agl. Exp. Sta. Rept. (1904): 



325-326. pi. 26. figs. a-c. 

 DUGGAR, B. M., and STEWART, F. C. The Sterile Fungus Rhizoctonia. 



Cornell University Agl. Exp. Sta. Built. 186: 50-76. figs. 15-23. 1901. 



Ibid. N. Y. (Geneva) Agl. Exp. Sta. Built. 186 : 4-30. figs. 15-23. 1901. 

 PAMMEL, L. H. Preliminary Notes on a Root-Rot Disease of Sugar Beets. 



Iowa Agl. Exp. Sta. Built. 15: 243-251. pis. 3-4. 1891. 

 ROLFS, F. M. Potato Failures. (Two Reports.) Colo. Agl. Exp. Sta. Bulks. 



70: 1-20. 1902; 91: 1-33. 1904. 

 ROLFS, F. M. (Tomato Diseases) Cortidum vagum (B. & C.). Fla. Agl. Exp. 



Sta. Rept. (1905): 46-47. 

 SORAUER, P. Pflanzenkrankheiten (2d ed.), /. c., 354-361. 



A fungus causing important diseases of the potato and perhaps 

 of a large number of other herbaceous and even woody plants has 

 recently been placed under the name above given. The various 



ifr9&3$*% 



^gj$ 



* ^jJv^ S 



FIG. 217. LETTUCE SEEDLINGS ATTACKED BY RHIZOCTONIA 



plant diseases due to this fungus had formerly been referred to 

 the form genus Rhizoctonia, which is a genus established by 

 De Candolle in 1815, including certain sterile fungi occurring 

 upon the roots of plants. There are great difficulties in determin- 

 ing what might be considered species in forms which are re- 

 ferred to this form genus, and the Corticium stage has not yet 



