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isolated from the diseased plants, which is also found in acid 
soils. It is thought that the bacterium is intimately asso- 
ciated with the disease. The disease appears to lose its virul- 
ence in neutral or alkali soils. 
In connection with this disease it may be interesting to note 
the painstaking methods of the Japanese scientist, Dr. S. 
Takaishi, Chemist of the Fukuoka Station, who studied this 
disease in its relation to the soil, discovered that it was al- 
ways associated with an acid soil, the acidity being produced 
by excessive nitrogenous manuring. He also noticed that the 
diseased condition spread from the tip of the leaves down- 
ward, along the margins — the course followed by the dew 
deposited on the leaves when it was heavy enough to form 
into drops. Large quantities of dew, in some cases as much 
as a liter, were gathered and carefully examined chemically 
and bacteriologically. Finally the organism mentioned above 
was discovered. Pure cultures have been secured and further 
experiments are now under way. 
Remedial measures for the control of the disease have con- 
sisted largely of neutralizing the soil and avoiding acid 
manures. 
5. Rice Smuts. Two smuts do considerable damage to the 
rice — 1, Ustilaginoidea virens (Cooke) Tak. (Japanese Ine- 
Koji), with very small spores; another, Tilletia horrida Tak. 
(Japanese Sumi-Kurobo), with larger spores. Nothing is 
done to control these diseases except the treating of the seed 
by dipping in water at 130 degrees F., for five minutes. 
The above are only the more serious diseases of rice in 
Japan. Seventy-six distinct diseases have been recognized 
and described. 
The introduction of any of these destructive plant diseases 
is perhaps more to be feared than the introduction of insect 
pests, and it should be a matter of serious concern to our quaran- 
tine officers. 
The writer had abundant opportunity to study the disease 
in the field and in the laboratory ; only lack of pathological 
training prevented him from going more fully into the sub- 
ject. A great deal has been published on these subjects, but 
unfortunately most of it is in the Japanese language. Copies 
of the more important bulletins were provided, and are sub- 
mitted herewith. A reference was given to a paper entitled 
‘‘Studies of the Parasitic Fungi of Rice in Japan,” by I. 
Miyake, Bot. Mag. of Japan (Tokyo), Vol. 23, March and 
April, 1909 ; but I was unable to secure copies. 
(To be continued.) 
