47 
cage with apple leaves for food. August 1 several small parasitic 
insects had formed cocoons within the cage. August 5, several 
worms dead. They become rigid, somewhat shrunken, lighter in 
color, and fall to the earth or rest on the leaves. No traces of 
the white muscardine in their body cavities. August 6, three 
dead larvae in the bottom of the cage show an external growth of 
Sporotrichum. The live worms rather sluggish. August 10, about 
thirty larvae dead with the white fungus removed and placed in 
bottle. Nearly all the worms are dead. August 11, a hymenop- 
terous parasite has emerged. August 13, fourteen worms with 
Sporotrichum removed and placed in bottle. August 22, a profuse 
growth of the white fungus on all the remaining larvae. Parasit< s 
dead and imbedded in the same fungus. 
A check to this experiment, of an equal number of fall web- 
worms, placed in a cage July 28 and kept under precisely similar 
conditions, except as to infection, remained without loss from 
fungous disease, the larvae pupating in due season and remain¬ 
ing in good condition. 
No. 38. August 24. Infection experiment upon fall web-worms 
from wild cherry, placed in cage used for experiment No. 37. No 
Sporotrichum spores were introduced artificially, and the larvae 
were subject to infection only from geims left by the former oc¬ 
cupants of the cage. September 10, one larva dead and covered 
with Sporotrichum. Several hymenopterous parasites have 
emerged. September 14, other larvae dead, but no fungus visible 
on their bodies; still others dead on the 17th; no more fungus. 
Experiment closed. 
Nos. 39 and 40. June 9. Cultures on sawdust saturated with 
beef broth and infected with fung is spores from culture No. 14. 
Beef broth prepared as in No. 78; sawdust heated almost to 
scorching; broth and sawdust mixed to a pasty consistency, put in 
test-tubes, and sterilized for half an hour in an oven at a temperature 
varying from 100 to 108° Cent. Treated with spores June 11, 
July 13, 8:10 a. m., spores have begun to grow. Growth more 
prominent on the 14th and 15th, and spreading freely the 16th. 
June 17, air spaces in the medium filled in the lower part 
of the tubes. Less than half the surface covered with the fungus. 
Very slight change by the 18th and 19th. June 20, fungus yel¬ 
lowish and highly granular. June 22, spores not easily detached; 
nearly the same condition on the 24th. Successful cultures, but of 
relatively slow and scanty growth. 
No. 41. June 9. Culture experiment identical with Nos. 39 and 
40, begun at the same time, varying only in the culture medium 
used, w T hich was a batter of middlings mixed with beef broth. 
The spores used (June 11) were from culture 14. Growth had 
started on the 13th, was increasing freely by the 14th, and was 
spreading noticeably on the 15th. Spores were forming by the 
17th, and by the 18th most of the surface was covered. Tinged 
with yellow on the 20th and spores ripe on the 22d. Easily de¬ 
tached by shaking. 
