68 Bulletin 186. 



The brown mycelial tlireads of the fungus among the diseased leaf 

 bases are evndent to the unaided eye, and after the root has become 

 affected, a considerable mycelial weft may be found in the cracks 

 and affected parts. A diseased beet sliced length w^ise and placed in 

 a moist chamber yields in a day or two a luxuriant growth of the 

 fungus. 



This disease has since been reported to us in the central and the 

 western parts of the State, but specimens were not seen. During 

 the past season it was found again, in the month of August, at Flint 

 and at Phelps, N. Y. ; but in neither case was there any serious out- 

 break of the disease. Specimens collected at the former place 

 showed a considerable development of sclerotia, which bodies had 

 not been previously observed upon the beet. Furthermore, Mr. A. 

 D. Selby has kindly told us that he has found this disease of beets 

 in Ohio during the past autumn. 



Inoculation experiments have been made in the field, and these 

 all indicate beyond a doubt that this Rhizoctonia may readily pro- 

 duce beet root-rot when the conditions are favorable. Moist con- 

 ditions are essential for the spread of the disease from plant to 

 plant. Morever, this fungus taken directly from diseased beets has 

 the power of damping off lettuce and also beet seedlings. 



A beet disease due to a species of Rhizoctonia has been known 

 to botanists in Europe since 1855 ; and we are indebted to Professor 

 Karl von Tubeuf, of Berlin, for material of that fungus. It is 

 improbable that the American form is identical witli the European. 

 However, the disease found by PammeP in Iowa may be the same 

 as the one which we find in New York. ' 



On the Cabbage and Cauliflower, Brassica oleracea. 



Specimens of diseased cabbage seedlings were received from 

 Cairo, 111., early in 1898. Among growers this disease is improperly 

 called black rot. Sometimes the disease affects very young seed- 

 lings, and they are damped off' by it, but it is more common after 

 the plantlets have developed one or two true leaves. In the latter, 

 ulcerated areas at or below the surface of the soil often characterize 



* Pammel, L. H. — Loc. cit. 



