24 
NEIL E. STEVENS 
temperatures on the other hand are not necessary is shown by the fact 
that ascospores developed at many stations between December, 19 14, 
and May, 1915, and at Washington Junction, Md., between December 
26, 1 914, and February 15, 191 5. Certainly (see Tables IX and X) 
the difference between the summer temperatures of 1914 and of 191 5 
is so slight that the failure of perithecia to develop in the first summer 
and their abundance in the second summer cannot be due to the dif- 
ference in temperature. 
Table X 
Monthly Temperature Summations for Various Localities 
Char- 
lottes- 
ville, 
Va. 
Wash- 
ington, 
D. C. 
Fred- 
erick, 
Md 
Wood- 
stock, 
Md. 
Wil- 
ming- 
ton, 
Del. 
Hart- 
foid, 
Conn. 
Mohonk 
Lake. 
N. Y. 
Am- 
herst, 
N. Y. 
Wil- 
liams- 
town, 
Mass. 
Con- 
cord, 
N. H, 
I9I4 
May 
717 
663 
639 
716 
540 
489 
439 
408 
345 
June 
921 
870 
870 
858 
880 
618 
599 
590 
557 
539 
July 
1,000 
960 
952 
934 
970 
757 
702 
737 
707 
684 
August 
1,048 
892 
931 
952 
998 
825 
745 
770 
676 
676 
September. . . 
672 
643 
584 
591 
712 
541 
549 
488 
404 
441 
October 
480 
481 
432 
443 
507 
341 
347 
313 
74 
232 
November . . . 
188 
138 
100 
125 
143 
67 
26 
29 
18 
23 
December.. . . 
25 
36 
31 
36 
29 
8 
14 
3 
II 
0 
1915 
January 
8 
18 
6 
12 
17 
10 
0 
0 
2 
0 
February .... 
40 
33 
12 
19 
35 
I 
0 
0 
2 
0 
March 
18 
4 
2 
5 
II 
3 
0 
0 
0 
0 
April 
501 
449 
432 
430 
426 
228 
281 
228 
238 
163 
May 
604 
549 
512 
523 
539 
338 
281 
290 
232 
198 
June 
760 
774 
754 
718 
736 
640 
561 
590 
591 
514 
July 
993 
973 
963 
869 
1,014 
807 
716 
779 
727 
720 
August 
899 
905 
881 
885 
923 
743 
641 
703 
622 
644 
Moisture 
There seems, however, to be a fairly constant relation between 
the appearance of perithecia and the amount of precipitation, or more 
properly the amount of moisture in the air. For convenience in 
reference a * has been placed in Table III to indicate the month in 
which ascospores were first observed at the various stations. At 
many localities perithecia were first noted in the spring, a season which 
of course is characterized by high humidity. In each case in which 
ascospores were produced during the summer the preceding months 
were characterized by abundant rainfall. July, 1915, at Concord, 
Williamstown, and Amherst, showed over 9 inches of rain and the 
perithecial production was correspondingly abundant. 
