(Vor. 8 
46 ANNALS OF THE MISSOURI BOTANICAL GARDEN 
intensified, the experiments below were arranged. A piece of 
agar with mycelium was placed in the soil at a distance of about 
1 inch from a plant to be inoculated. No wound was made. 
TABLE XXXIII 
INOCULATION WITH REISOLATED STRAINS OF P1 
Plants inoculated | Reis. strain from No. plants | No. infected | Remarks 
Potato 10 7 Stem- 
lesion 
Lettuce 10 5 Stem- 
lesion 
Potato (1.5" high) Egg-plant 10 4 Stem- 
lesion 
Navy beans 10 6 Stem- 
lesion 
Lima beans 10 4 Stem- 
lesion 
Potato 20 19 
Lettuce 10 19 
Lettuce (about 2") Egg-plant 10 18 
Navy beans 18 14 
Lima beans 17 9 
Potato 20 10 
Lettuce 20 12 
Egg-plant Egg-plant 20 15 
(about 2") Navy beans 20 13 
Lima beans 20 9 
Potato 15 6 
Lettuce 13 6 
Navy beans Egg-plant 15 6 
Navy beans 15 9 
Lima beans « 15 8 
As shown by the table, the pathogenicity of the fungus is more 
or less modified by changing the host plants on which it lives. 
The highest pathogenie efficiency is always secured when an 
inoculation is made on plants belonging to the same species as 
the host from which the inoculation material originated. 
PARASITISM OF RHIZOCTONIA, WITH SPECIAL REFERENCE TO 
PENETRATION OF HYPHAE 
Concerning the nature of parasitism in Rhizoctonia, Drayton 
(15), in his microscopical examination of transverse and longi- 
