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ked great havoc in the pea-district, causing an exten- 
sive wilt which usually reached its maximum about 
midsummer (hence the name). The fungus attacked the 
roots and spread itself through the bark and pith. In- 
fection experiments with pure cultures of the fungus- 
gave positive results; when living mycelium was app- 
lied to the neck of the root a rapid breaking down of 
the tissues followed, and the plant wilted. Van Hall 
called the fungus Fusarium vasinfectum var. Pisi. 
An extensive study of a pea-fusariose in Germany 
was published by Schikorra (3) in 1907. According to- 
him the disease is identical with that described by van 
Hall under the name of the St. John’s disease. He 
adopts van Hall’s name for the fungus. Schikorra’s de- 
scription of this pea-fusariose gives the picture of a 
typical wilt. At first scattered leaves begin to droop r 
but soon the whole plant becomes involved, and a com- 
plete wilting down takes place. Usually the leaves 
turn yellow, and the plant dries up quickly. A closer 
examination of the diseased plants showed discoloured 
areas at the base of the stem. Here the fungus was found 
traversing the bark and the central cylinder. Further up the 
stem it was confined to the vessels. The stopping of the 
water conduction is accomplished, according to Schikorra, 
by glistening gummy stuff, which is secreted by the fungus 
in large quantities. Pure cultures were obtained, and inocu- 
lations were made proving the pathogenicity of the fungus- 
Appel and Wollenweber (1), in their well-known 
researches into the taxonomy of the Fusaria, have con- 
tributed much to a better understanding of the problems 
involved. They prove that the fungi described by van 
Hall and Schikorra in their studies of St. John’s disease 
in peas are two different species, and they give the 
name of F . falcatum App. et Wr. to the species dealt 
with by Schikorra, while the name F. vasinfectum var „ 
Pisi. is retained for the fungus originally described by 
