The Nuptial Flight 103 
usually were at 4:30 on clear mornings, and instead of the flight 
stopping at the usual time, it continued for twenty minutes 
longer, or until 4:50; this point is interesting in that it demon- 
strates how much a slave to certain intensities of light these 
creatures are. In all, about 20 males were taken, a small num- 
ber, but sufficient to demonstrate conclusively that heavy rains 
do not deter their flight, and that after flying in the rain they 
are none the worse for wear. Since it had rained steadily from 
7 p. m. to 7 a. m. (1.6 inches of rain fell), this flight shows that 
the rain does not obliterate their medium of communication 
(odor?). All of the males were native ones that had never, been 
on the roof before. If one could prove that the action of this 
amount of rain could destroy the female odor or cause it to 
settle on or near the ground where it could not disseminate, and 
then if the males still flew to the cages, one would have to at- 
tribute the action to something other than odor. 
Exp. 29. May 26. Wind, east; station, 30 feet west, on 
ground. This experiment and the three that follow (also Poly- 
phemus Exp.) were conducted during the night of May 26-27, 
and are of especial interest because the moon shone for certain 
Periods during the night and the irregular and unusual flight 
of the moths correlated beautifully with the periods of moon- 
light. The intricacies of their reaction to intermittent and con- 
stant moonlight will be considered in detail later in these pages. 
ourteen male cecropias were liberated in the back yard on the 
ground, 30 feet west of the females, at 11:55 p. m., with the 
wind blowing directly toward them. Six of these came back, 
one at 12:05 (after only ten minutes), one at 1:25, three be- 
between 3:18 and 3:40, and the sixth one came in at dawn a day 
later. 
Exp. 30. May 26. Wind, east; station, 44 mile west. Thirty 
new native males and one which had made two previous flights 
were liberated a little further west and three minutes later than 
the last lot. Thirteen of these returned, the first three arrived 
22, 72 and 77 minutes after they were set free, nine came in 
between 3:40 and 4 a. m., and the experienced flier came in 
the next day at dawn. 
Exp. 31. May 26. Wind, east; station, 1 mile west. Thirteen 
males from 1 to 3 days old, which had emerged from cocoons in 
