The Nuptial Flight 141 
Summary. 
Polyphemus males did not show any reaction to the many 
cecropia and cynthia females on the roof. No males, either 
native or bred, ever came to the roof excepting when females 
of their own species were present. During the period of ex- 
perimentation, May 21 to June 18, 31 native males came in and 
went directly to the cages of their own species only. 
Tabulation of all the data* reveals that out of the 64 marked 
males that were liberated at various points, only 9 returned to 
the roof; 7 of these were inexperienced and 2 had had previous 
trips. On a percentage basis, we find that 10 per cent of those 
taken out for the first time and 8 per cent of those that had had 
previous experience, returned. These figures are too small to 
be significant, excepting that they indicate faintly that experi- 
ence is of no advantage. Of the 9 that did return, 4 came in 
during the first night, 3 the second night and 2 the third night. 
Tn the small number tested for long distance flights, even in a 
wind which seemed favorable to them, none returned from a dis- 
tance of 3 miles, or even 2 miles, but some did come back from 
¥, 1, 1%, and 134 mile points. The above evidence gives one an 
idea of what one may expect when more extensive work is done. 
It must be borne in mind that polyphemus are native to this re- 
gion, and undoubtedly many of our marked bred males flew to 
native females. Throughout the season the native polyphemus 
males did not come to the roof in such abundance as did the 
cecropias. We do not know whether this is because these moths 
9 not occur in such large numbers as the sister species, or 
Whether they are not responsive to the third-floor condition, 
which is probably above the normal level of their flight. 
The time consumed in making the trip to the roof from dis- 
tances varying from 14 to 34 miles varied from 1% to 40 hours. 
The normal time of flight of the eecropias was found to be 
(with a few exceptions under certain conditions) the hour of 
dawn; for cynthias, a period in the middle of the night and 
again at dawn. This species also has two distinct periods of 
activity, the hour before midnight and the hour of dawn. The 
hour of arrival of the 39 males, both native and bred, which flew 
to the roof, was as follows: 
ee 
*See Table 5. 
