46 BULLETIN 380, U. S. DEPARTMENT OF AGRICULTURE. 
At 85° C., Endothia gyrosa, E. singularis, and E. parasitica showed a slight 
development within 2 days, but at the end of 11 days it was still slight and 
abnormal in appearance. 2. fluens and HH. fluens mississippiensis showed no 
growth at this temperature. 
At 81° C., Endothia gyrosa, FE. singularis, and EF. parasitica appeared about 
the same as at room temperature for the first four days. At the end of six 
days these species showed somewhat less growth than at room temperature, 
while at the end of two weeks the growth was less in extent and markedly 
less freshly colored than that at room temperature. H. fluens and H. fluens 
mississippiensis showed somewhat less growth than at room temperature even 
in 4 days, and markedly less at the end of 2 weeks. 
At room temperature (which at this time varied from 20° to 24° ©.) the 
growth was much as described in the previous paper. Within 11 days growth 
was practically complete and in 14 days there was abundant spore production 
in EHndothia parasitica. 
At 18° and 16° C., all species showed considerably less growth than at room 
temperature, but there seems to be little difference in the comparative growth 
of the various species at these temperatures. At 13° the growth was decidedly 
less than at 16° C. but was fairly normal in appearance in all the species except 
that Endothia fluens mississippiensis failed to produce the characteristic color 
at this temperature. 
At 9° C. there was a very slight growth in all species. 
At 7°, 5°, and 2° ©, there was no growth whatever. Cultures removed to 
room temperature at the end of 11 days developed normally and at about the 
same rate as in newly made cultures. 
These additional tests seemed to confirm the results already pub- 
lished (77, p. 27) ; that is, growth was best in all species at ordinary 
room temperature, about 20° to 24° C. The minimum temperature 
for all was about 9°, and all failed to grow at 7° C. The maximum 
temperature for H'ndothia gyrosa, EF. singularis, and E. parasitica 
appeared to be about 35°, while the maximum for £. fluens and its 
variety Z’. fluens mississippiensis was apparently about 32° C. At 
all the temperatures tried Z’. singularis grew much more slowly than 
any of the other species. 
It was noted that cultures kept at 7°, 5°, and 2° C. showed no 
growth, but when removed to room temperature developed normally, 
while cultures kept at 41° and 39° C. failed to grow when removed to 
room temperature. This seemed to indicate that the fungi are more 
susceptible to heat than to cold, and such is perhaps the case. There 
was, however, the additional factor of moisture involved, for while 
the agar of the cultures kept at 7° and lower was in apparently the 
same condition at the end of 11 days as when first inoculated, the 
agar of the cultures kept at 41° to 39° C. was considerably dried. 
This raised the question as to whether the drying out of the agar had 
not affected the growth of the fungi in those cultures kept above room 
temperature as much as the higher temperatures themselves. 
The same idea was suggested by the fact that several of the species 
grew for a few days at 31° C. as well as they did at room temperature, 
and then fell behind. It seemed possible that this falling off in the 
