110 Trans. Acad. Sci. of St. Louis 
exactly parallel tests, the wild males which had flown to the 
roof at dawn of the same day were conspicuously more success- 
ful than their brothers who had come in similarly one or two 
days before. Out of 14 bred males, three days old, 4 returned; 
none of these waited for dawn, but all arrived between 12:15 
and 1:20 a.m. Of the 8 moths which had emerged the same 
day, two returned the same night at 11:40 and 1:20 o’clock, and 
two more came in two nights later. In the last lot of mated 
males, 2 out of 9 returned the same night at 11:20 and 12:50. 
This shows, again, that even after having mated, the moths 
respond to the attraction of the females for a distance of at 
least half a mile. Thus, out of the total of 65 that were liberated, 
20, or 31 per cent, returned ; 18 of these came the first night and 
2 later. 
Exp. 52. June 4. In addition to the marked moths that 
came in as recorded in the last experiment, during the night of 
June 4-5, 9 new wild males flew in. They did not wait, this time, 
for the usual hour of flight, but they were well distributed 
throughout the night, from 10:30 until dawn. The cecropia 
season was drawing to a close. From our cocoons in the labora- 
tory, only 22 emerged from June 5 to 8, and none at all after 
that. 
Exp. 53. June 6. During the hour of dawn, 7 wild moths 
and 1 marked one (already accounted for) came in from the 
north. The breeze was from the south. 
Exp. 54. June 7. Being badly in need of sleep, I did not 
get up during the night to receive the eager lovers, but at 7 
a.m. I found 6 wild cecropias (4 old and 2 young) at the cages. 
Exp. 55. June 9. Wind, northeast; station, 14 mile south. 
Several cages full of cecropia females, two and three days old, 
were exposed to the gentle breeze on the roof. Three males, 
each with one-half of each antenna removed, were liberated at 
9:14 p. m., 14 mile south, a little to one side of the path of the 
wind. At the following dawn, one of these came back. 
Exp. 56. June 10. During the customary hour of flight, 25 
wild cecropias came in. All of these males were young. This 
large number, at the end of the season, would indicate that 
native females are scarce or too old to be attractive. : 
Exp. 57. June 11. The rain of the previous day continued, — 
