RELATION BETWEEN VEGETATIVE VIGOR AND REPRODUCTION 547 
from various solutions were transferred February 14, 1913 to 0.05 
percent haemoglobin and to haemoglobin and salts, one set being 
kept in the laboratory where the temperature ranged from 20° to 
23° C. and often higher while another set was kept in the basement 
of the writer's home at a temperature varying between 14° and 18° C. 
Production of sporangia. — -The optimum temperature conditions 
for the production of sporangia are quite different, a high temperature 
causing the sporangia to develop more rapidly than a low one. Klebs 
found this to be the case in S. mixta also. At a temperature of 28° C. 
S. ferax formed young sporangia in five and one-half hours and these 
were discharged in seven hours from the time the mycelium was put 
into water. A duplicate lot from the same culture, kept at laboratory 
temperature (about 20° C. at that time), formed young sporangia in 
seven hours and these were discharged in nine hours. The maximum 
temperature at which sporangia were formed in this species was 
30°+ C. at which some swarming took place in six and three quarter 
hours but the spores left the sporangium slowly and were evidently 
feeble. In another test duplicate lots of mycelium were placed in 
water at 28° C, at laboratory temperature i8°-20° C, and in an ice 
box where the temperature was between 6° and 8° C. Table VII 
shows at the same time the effect of the higher temperature on the 
production of sporangia and also the relative number of sporangia 
formed in mycelia out of different foods. 
Table VII 
S. ferax. Mycelia Out of Media Under Column i. Transferred to Water at Different 
Temperatures for the Production of Sporangia 
I 
3 
4 
5 
At 28°. 
16 Hrs. 
18O-20O. 
16 Hrs. 
6O-8O. 16 Hrs. 
6°-80. 22 Hrs. 
Peptone 0.1%, 
sucrose 1%, 
salts 0.1% 
Peptone 2% 
Peptone 0.5% 
Peptone 0.1% ....... . 
Peptone 0.05%. ...... 
Peptone 0.01% 
Peptone 0.1% 
Peptone 0.1% 
+ salts 0.1% 
Ill 
III 
11 + 
11 + 
I 
o-I 
III 
III 
Ill 
III 
11 + 
11 + 
I 
0 
II 
III 
II, none discharged 
I, none discharged 
I, none discharged 
I, none discharged 
0 
0 
o-I, none discharged 
o-I, none discharged 
Ill, just discharging. 
I, none discharged. 
I, a few discharged. 
I-II, a few dis- 
charged. 
0- I, a few discharged. 
0, a few discharged. 
1- II, discharging. 
1, discharging. 
