Experiments in Rhythmetic Periodicity 157 
way to the light end. At 11:10 I approached cautiously and 
fanned a current of air over the cage of females and toward 
the males in the dark end of the box. Almost immediately many 
wings began to quiver, and in five minutes 13 more had 
wandered to the lighted pane. The fanning was continued only 
at intervals, but up to 8 o’clock no more had responded. This 
shows that the males may remain in the presence of female odor 
plus light and only 6 out of 41 stir in three hours, whereas in 
female odor plus light plus breeze, 13 more respond within five 
minutes. But in this test again where moths bred in the labora- 
tory were used, more than half of the males failed to react at 
all. How is this to be explained? Are these laggards the stupid 
ones which Nature would eliminate in the wi 
Exp. 4. June 3, 2:30 p. m. Thirteen young males were 
gently placed in the box with 32 females; all were quiet at the 
time. Heretofore, the females when placed in the glass box had 
been enclosed in a wire cage, but this time they were all placed 
together free. For 45 minutes there was no reaction of any kind 
by any of the moths of either sex. Then I began to fan the 
group gently with a folded newspaper; after about five minutes 
of this a few males awakened to gentle response, and then two 
females; in ten minutes more, five females were participating in 
wild fluttering, and three of these had done just as the males 
in previous tests had done in fluttering to the light end of the 
box, and there beating their heads and wings against the glass 
nearest the light. Whenever their activity lessened or ceased, 
a little fanning would quickly arouse them to renewed activity. 
This experiment shows, as did some of the previous ones, that 
some females do show aggressiveness, react to light vibrations, 
and possibly also are influenced by the emanations of the op- 
posite sex, just as are the males. 
Electric Fan Experiments. 
In the foregoing experiments we have seen how, ordinarily, 
quiet moths are not influenced to activity by the presence of the 
opposite sex in close quarters until a breeze, either artifically 
induced or naturally ereated by the flapping of wings, dissemin- 
ates the odor. The following supplementary experiments were 
made upon moths of both sexes in separate cages placed before 
