70 
showed any traces of fungus on their bodies. By the 31st those 
which were of a pinkish tint at first had become covered with a 
whitish mycelium. Several imagos emerged April 2. Two more 
dead pupae of a pinkish tint were seen the 4th. Several other 
dead larvae and pupae were seen at this time, but no fuDgus was 
present on them. On the 5th two more pinkish larvae were seen. 
Nearly one third of the larvae had now become imagos. By the 
7th a whitish growth of fungus of a pinkish tint had appeared on 
all the larvae and pupae, and spores had begun to form by the 
12th, being apparently ripe on one specimen by the 14th. 
A number of larvae from the same source were kept under sim¬ 
ilar conditions as a check. No fungus appeared in the check at 
any time, and nearly all had emerged as imagos by April 14. 
No. 12. March 31. Fifty white grubs (most of them Poly - 
mcechus brevipes and the remainder Serica vespertina) taken 
from a rotten oak log at Urbana, Ill., were thoroughly dusted with 
a portion of the contents of one of the tubes from Fribourg & Hesse, 
and were placed in an earthen dish with a quantity of the rotten 
wood. A check lot was established under similar conditions, but 
not dusted with spores. The first effect of the treatment was ob¬ 
served April (5, when a single larva each of Serica and Polymoechus 
was found dead, the latter with a flabby thorax and the abdomen 
somewhat hard. This lot of larvae was examined at intervals of 
two days, and April 8 one more was found dead, April 10 sixteen, 
on the 12th seventeen, on the 14th one, on the 16th three, on the 
18th four, and finally, May 2, five more—making forty-nine in all. 
Infection by this fungus is unmistakably indicated by a pale 
pink tint of the dead larvae, deepening to a definite rosy color, 
which disappears, however, with the development of spores upon 
the surface of the grub. This characteristic color was shown by 
twenty of the above larvae, the first exhibiting it April 8. It was 
noticed that the Serica larvae, although seemingly affected like the 
others, did not change color in this way. An external mycelium 
was first shown April 16, on a grub which had died on the 8th 
and had then been transferred to damp sand and covered with a 
bell-jar. Others showed this external growth on the 18th and 20th, 
while spores first appeared April 26. From such spores success¬ 
ful cultures were made in test-tubes of agar-agar, the culture 
medium assuming the deep red color to which this fungus gives 
rise. Proof was consequently complete of the destruction of at 
least a considerable number of these grub 3 by a thorough infection 
with spores of Botrytis tenellci. In the check, in the mean time, 
three larvae had died, one on the 14th and two on the 18th of April 
—all of them, however, without any appearance of fungous affection. 
No. 13. May 7. Several test-tube agar cultures, the spores 
derived from one of the white grubs dead as described in exper¬ 
iment 12. Visible growth of Botrytis in two days, but an impure 
culture in every tube. Contaminated with bacteria and various 
foreign fungi. Several of these tubes were thrown out, but from 
one all the growths not resembling Botrytis were removed with 
sterilized tools, and the glass above the agar was heated in the 
