New YorK AGRICULTURAL EXPERIMENT STATION. 101 
to be devoid of protoplasm, and from neighboring protoplasmic 
cells the germ tubes seem to pass into such empty cells as read. 
ily as directly into the nutrient solution. When the germ tube 
is from 10, to 20, in length, it is invariably narrowed towards 
the outlet from the parent cell, and a septum forms at a short 
distance from this outlet, as in Fig. 4. Large, irregular, sclero- 
tial bodies are sometimes found upon the beet, but they are by 
no means of constant occurrence. 
If a part of a diseased beet is placed in a moist chamber, a 
loose mycelial growth soon appears, and the threads may grow 
out to the extent of half an inch or so. From this it is an easy 
matter to obtain a pure culture by transferring some of this 
mycelium to acidulated agar in petri dishes. The fungus grows 
readily upon acidulated agar, while bacteria are for the most 
part excluded. The fungus may then be transferred to bean pods, 
or beet plugs, in test tubes, upon both of which media most 
forms of Rhizoctonia seem to grow well. In pure culture a loose 
mycelial growth first appears. This becomes brown in time. A 
short tufted growth may appear later; and usually there is also 
an effuse or crust-like sclerotial development. In culture the 
sclerotia are usually irregular in form and brown in color. 
At this time it is not desired to enter into a discussion of the 
slightly different morphological characters which may distinguish 
the different forms of Rhizoctonia. 
BRIEF NOTES UPON RHIZOCTONIA IN BUROPR, 
(Historical.) 
The root-destroying fungus Rhizoctonia was first discovered 
by De Candolle! in 1815. He named two species: Rhizoctonia 
medicagimis, occurring on Medicago, Trifolium and related hosts; 
and R. crocorum, a fungus destructive to crocus bulbs. Of the 
brief notes published upon other species of the fungus and other 
host plants until 1851, a comprehensive summary is given by the 
brothers Tulasne.2? They believed that the several species then 

*De Candolle—Mem. d. Mus.-d’hist. nat., 1815. 
*Tulasne, L, et C.—Fungi Hypogaei, pp. 188-195, 1851. 
