New York AGRICULTURAL EXPERIMENT STATION. 143 
brown in color. When the hyphe occur in scab ulcers, those 
near the surface are brown, while the deeper-lying ones are color- 
less. The sclerotia on the stems and those on the tubers are 
essentially the same. They are irregular in outline and vary in 
size from a mere speck to the size of half a pea or even larger. 
When dry they are dirt colored, and it is difficult to distinguish 
them from particles of soil adhering to the tubers. This prob- 
ably accounts for their having been so generally overlooked. But 
when wet they become dark brown and very conspicuous, - par- 
ticularly on the light skinned varieties of potatoes. In spite of 
vigorous washing, sufficient to thoroughly remove the soil from 
the tubers, the sclerotia remain firmly attached. Two house- 
_ keepers whose attention we have called to the matter assure us 
that they have long observed that when potatoes are prepared 
for baking there are often found dark brown irregular bodies 
which are exceedingly difficult to remove by washing. It is neces- 
sary to use a scrubbing brush to get rid of them. We suspect 
that these sclerotia are well known to many of the more observant 
housekeepers. 
The amount of damage done by the Rhizoctonia when it attacks 
the subterranean stem and roots of the potato is as yet undeter- 
mined, but that the fungus is, in some cases at least, a parasite 
there is little doubt. Where it occurs on the tubers, all of our 
numerous observations go to show that it is not injurious to 
them. While the Rhizoctonia hyphe may be abundant in scab 
ulcers there is no evidence that they have anything to do with 
the formation of the ulcers. The sclerotia are usually seated 
on the uninjured skin of the tuber. <A tuber may bear hun- 
dreds of sclerotia and yet be absolutely sound. In this respect 
our Rhizoctonia appears to differ from the European potato 
Rhizoctonia. Some writers report that the latter is a common 
cause of potato rot. In other respects the two forms are strik- 
ingly similar. We are under obligations to Prof. Dr. Paul 
Sorauer of Berlin for excellent fresh specimens of the European 
Rivzoctonia solani, from which cultures for inoculation work have. 
been obtained. Ai) shew 
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8 % 
