108 REPORT OF THE BOTANIST OF THB 
the latter instance the owner stated that he had had much trouble 
from damping off. In both of these cases Rhizoctonia was 
undoubtedly the sole cause of the trouble. Weare informed that 
the damping off of celery seedlings is a common occurrence, ‘but 
thus far we have had opportunity to investigate only the two 
cases above mentioned. 
ON THD COTTON. 
(Gossypium herbaceum.) 
The Rhizoctonia which is the cause of “ sore-shin ” or damping 
off of cotton seedlings has not yet been secured by us; but Pro- 
fessor Atkinson has kindly put at our disposal drawings which 
he made while studying this fungus in Alabama. He first 
reported upon it under the caption “ sore-shin” in Bulletin 41 
of the Ala. Agl. Exp. Sta. In describing it, he says: “The 
diseased portion of the plant is just beneath the surface of the 
ground, and is characterized by a shrunken area of a dull red- 
dish-brown color. * * * If the injury remains confined to the 
superficial tissues, the plant may, and frequently does, recover.” 
The sterile fungus concerned with this disease was isolated, and 
inoculation experiments demonstrated that the fungus secured 
was the cause of the damping-off. The description of the fun- 
gus in the above mentioned bulletin and the drawings which we 
have, demonstrate beyond a doubt that the fungus is a form of 
Rhizoctonia. 
ON THE LETTUCR, 
(Lactuca satiwa.) 
Since 1896 we have repeatedly found lettuce seedlings damp- 
ing off by a sterile fungus; but it was not until 1898 that it was 
particularly studied, or its affinities ascertained, and the fungus 
located as Rhizoctonia. Lettuce seedlings affected by this fun-. 
gus have much the same appearance as seedlings affected by any 
damping-off fungus. At or near the surface of the ground the 
tissues become water-soaked in appearance, they are unable 
longer to support the plantlet, and it falls prostrate on the sur- 
face of the ground, the fungus soon invading all parts. This 
