456 
JOHN A. ELLIOTT 
jars for the first few days following inoculations. Inoculations were 
attempted on cantaloupe {Cucumis melo), cabbage, Datura, and Lac- 
tuca. Characteristic spots were produced on cantaloupe in all cases; 
25 percent of the inoculations on cabbage were successful; no spots 
were formed on Lactuca or Datura. 
The spots produced on cantaloupe leaves, appearing in 2 or 3 days, 
developed rapidly. The spots on cabbage leaves were mere dots 
where the spores had germinated on the unbroken leaf surface, but of 
considerable size where punctures were made. No spores were pro- 
duced on cabbage and very few on cantaloupe leaves. 
A. hrassicae var. microspora from cabbage leaf spots: All inocula- 
tions were made with spores from pure cultures, by needle pricks or on 
the unbroken leaf surface. Inoculations were attempted on cabbage, 
radish {Raphanus sativus L.), Lohularia maritima (L.) Desv., Dianthus, 
potato, Datura, tomato leaves and fruit. On all cruciferous plants the 
fungus produced characteristic concentric spots with dark rings of 
spores on the surface. Spores spread the fungus to other parts of 
susceptible plants until they were entirely destroyed. On ripe to- 
matoes dark spots were formed with narrow sharply defined zones of 
spores. No spots were formed on the other plants used. 
A. fasciculata from potato leaf spots: Inoculations were made with 
spores by means of needle pricks and on the unbroken leaf surface. 
The plants inoculated were: potato, tomato leaves and fruit, cabbage, 
radish, Dianthus. 
The only definite spots of parasitic appearance were from needle 
pricks on etiolated or partially etiolated cabbage leaves. The spores 
and conidiophores on the cabbage leaf spots were very light amber in 
color, instead of dark olive as is normal. In ripe tomatoes a hard 
black core was formed in the interior as the mycelium invaded the 
tissues. This was surrounded by a soft decayed area. The inocu- 
lations failed on the other plants. 
A. tenuis from decaying wood: Only one series of inoculations was 
attempted with this species. This was made on Dianthus leaves by 
means of needle pricks. No spots were formed. The inoculations 
were made on Dianthus because A. tenuis spores cannot be distin- 
guished from those of A. dianthi. 
A . dianthi from Dianthus leaf spots : Inoculations were made both 
by needle pricks and on unwounded leaf surface with spores of the 
first and fifth generations from agar plates. Dianthus and cabbage 
