130 
Mycologia 
to dextrose agar. The results of these germination tests are 
shown in Table III. The slight reduction in germination per- 
TABLE III 
Germination Percentages of Ascospores Expelled from Desiccated Bark 
Specimen Number 
Period of Desiccation 
Germination Per- 
centages 
Average Germination 
Percentages 
341 
341 
5 mo., 9 days 
98 
98.5 
98.25 
345 
345 
5 mo., 9 days 
86.75 
85.8 
86.27 
349 
6 mo., 13 days 
59 
61 
349 
63 
350 
350 
6 mo., 13 days 
81.5 
84 
82.25 
373 
373 
8 mo., 17 days 
69.7 
68.9 
69-3 
392 
392 
10 mo., 14 days 
50 
29.16 
36.58 
393 
393 
10 mo., 14 days 
78 
77-8 
77-9 
centage is in agreement with the results reported by Anderson 
and Rankin for ascospores under the conditions of their tests. 
Conclusions 
Continued desiccation does not inhibit the power of the peri- 
thecia of Endothia parasitica to expel spores when subjected to 
favorable conditions of temperature and moisture. It does, how- 
ever, lengthen the period from the beginning of favorable condi- 
tions to the first expulsion. On account of this fact, it does not 
seem probable that perithecial material which has been retained 
in a dry condition for three months or more would ever be sub- 
jected under natural conditions to favorable influences for a suffi- 
cient length of time to induce spore expulsion. IMaterial dried 
for one or two months, might, however, be a source of danger, 
as more or less expulsion might be induced by natural agencies. 
Spores expelled from desiccated perithecia show little or no 
reduction in the percentage of germination. 
It seems probable from our results and from those of others 
already cited that the time limit of ability to expel ascospores 
was not reached in the tests here recorded. 
