THOMAS: INFECTION OF APIUM GRAVEOLENS 3 
Duggar and Bailey (10), Clinton (5 p. 267),.and Link and Gard- 
ner (19) have observed that both celery and celeriac are attacked 
by Septoria in storage. The first authors noted that over 50 per 
cent of the stored ids was made unsalable by this fungus in 
one instance. 
No extensive observations seem to have been made on the 
degree of susceptibility of the commercial varieties of celery to 
the late blight. Salmon (4) tested several varieties and arranged 
them in the following series, the first being most susceptible: 
Solid White, Clark’s Early Market, Superb Pink, Giant Red, 
Standard Bearer, celeriac. Howitt (4) noted that Golden Self 
Blanching was particularly susceptible. White (42) concluded 
in general that Golden Self Blanching was very susceptible to 
disease while Henderson’s Easy Blanching was comparatively free 
from disease. On wild celery Pethybridge (26) found fewer and 
smaller spots produced by Septoria, which seemed never to kill 
the leaf entirely. He states that the fungus occurs on parsley 
though rarely in the British Isles. Cooke (7) and others have 
considered the forms on celery and parsley identical, although I 
have found no record of the transfer of the Septoria from one of 
these hosts to the others. 
Some interesting observations were made by Kinney (16) on 
the relation of cultural practice to blights of celery. He found 
that the amount of disease was reduced by mulching with seaweed, 
soil, coarse manure or even blighted leaves. Plants grown in the 
shade of trees seemed to be less subject to “‘blight.’”’ Unfortu- 
nately the author did not distinguish between Septoria and Corco- 
spora blight. Zobel (43) believes that reduction of the amount of 
manure in the trenches and top dressing the soil with kainit 
greatly reduced the amount of Septoria in England. 
Attempts to avoid or control the late blight, while not uni- 
formly successful, are in practical agreement in the essentials. 
Rogers (31), Salmon (34), Howitt (14), Coons and Levin (8), and 
Krout (18) obtained ae control of the disease with Bordeaux 
mixture. 
MATERIALS AND METHODS 
I have attacked the problem of the relation of health, age and 
other conditions to susceptibility by means of inoculation experi- 
