107 
Nos. 25, 26, and 27. July 31. Dead cabbage worms as above. 
Experiments identical with the foregoing, and made at the same 
date, except that infected spots were touched with sterilized dis¬ 
tilled water to cause the spores to adhere to the worm. The re¬ 
sults were all as above mentioned, with a slight variation in No. 
■27. Here, August 1, no growth of the spores had appeared, but 
one larva had become fastened to the cover by a fine white web. 
On the 2d the growth was spreading feebly, and on the 3d the 
worms were turning crushed-raspberry color, the one on the cover 
having the Sporotrichum growth well started. August 7, this fungus 
was fully developed on all, and the specimens were put aside for 
preservation. 
No. 28. July 31, 10 a. m. Three pupae of cabbage worms 
placed under same conditions as No. 21, and infected with Sporo¬ 
trichum from No. 11. August 1, no growth. August 2, two of 
the pupae turning reddish, but no growth. August 3, still no 
growth, but one of the pupae of a deep red tint. August 7, two 
of the pupae dead, one of them showing a slight mycelial growth 
of Sporotrichum. The third has yielded a healthy butterfly. 
Nos. 29 to 35 are agar test-tube cultures, in which the gelatine 
was acidulated variously, it being the purpose of these experiments 
to determine the degree of acidity of the medium most favorable 
to the germination of the spores and the development of the 
fungus. 
No. 29. August 2, 3f cc. of agar gelatine and \ cc. of a one 
eighth per cent, solution of acetic acid in test-tube, sown with 
spores of Sporotrichum glohulijerunj, from No. 11. August 13, no 
Sporotrichum growing, spores apparently not having started. 
No. 30. August 2. Like 29, except that the acetic acid was in 
a one fourth per cent, solution. August 13 there has been appar¬ 
ently a slight growth of Sporotrichum in this tube, but it is now 
all dead. 
No. 31. August 2. Like 29, except that the acetic acid used 
was a one half per cent, solution. August 13, a small straggling 
growth of Sporotrichum has appeared and has formed spores. 
No. 32. August 2. As above, except that the acetic acid was a 
one per cent, solution. August 13, fair growth of Sporotrichum, 
covering most of the agar surface. Spores abundant, ripe, but not 
of yellowish tint. 
No. 33. August 2. As above, but acetic acid now a two per 
cent, solution. Hesult identical with no 32. 
No. 34. August 2. Like no 29, except that the acetic acid is 
now a five per cent, solution. August 13, no growth whatever. 
No. 35. Like No. 29, except that the acetic acid used was a 
ten per cent, solution. August 13, no growth. 
From the foregoing it appears that an agar mixture containing 
from three to six hundredths of one per cent, of acetic acid is that 
which proved most favorable to the growing of Sporotrichum. These 
experiments should be repeated, however, for verification before 
the statement is accepted. 
