PROGRESS REPORT ON THE EUROPEAN CORN BORER HI 
The moths are most active during warm nights and comparatively 
inactive on cool or cold nights or during heavy winds. The daily 
period of greatest flight activity begins shortly after dusk and does 
not materially decrease until after three or four hours of darkness. 
Only a few moths have been observed in flight during the later 
hours of the night, although this observation may have been in- 
fluenced by the difficulty of observing the moths at this period. 
During the month of June the moths were most active in laboratory 
cages from 9 p. m. until about 11 p. m. and more or less active 
until 4.30 a, m. 
The flight of the sexes is somewhat different in character. Since 
the female is heavier her flight is direct, while that of the male is 
more rapid and of an erratic zig-zag character. 
DISTANCE OF FLIGHT 
In the course of experiments to determine the flight abilities of 
the moths it was found that both sexes possess the power of sustained 
flight for considerable distances either in single flights or in a series 
of flights. Flight usually occurs in the direction of the prevailing 
wind, although moths have been observed flying against a light 
wind. 
Previously it has been stated that when dislodged during the day 
the moths usually fly only a few feet before seeking shelter. During 
their daily period of active crepuscular flight, however, certain of 
the moths fly much longer distances, although it was not possible 
accurately to gauge the distance of such flights because of the dim 
light. In order, therefore, to obtain indicative information regard- 
ing the flight capabilities of moths in single flights it was necessary 
to liberate moths during the day in situations where shelter was 
absent. For this purpose a stretch of low, wide, sandy beach was 
selected, which was devoid of shelter within 200 yards, and moths of 
both sexes were liberated at the edge of the water during low tide at 
a time when a light breeze was blowing off the water. Under 
these conditions individual moths were traced in single flights in the 
direction of the prevailing breeze for a maximum distance of 258 
yards and to an elevation of approximately 50 feet before they were 
lost to view. All of the moths used in this experiment took flight 
directly after liberation and flew rapidly with the prevailing breeze, 
gradually ascending to elevations of from 15 to 50 feet before being 
lost to view. At this point they were flying strongly, and it seems 
probable that they covered at least 300 yeards from the point of 
liberation before alighting. 
In these and in similar experiments, little difference was observed 
between the flight capabilities of the sexes. The males as a rule took 
flight quicker than the females after liberation and flew more rap- 
idly, but the females were more direct in their flight and appeared 
to cover at least an equal distance. All of the females used in these 
experiments were gravid. 
Flight Experiment on Cape Cod 
Prior to the summer of 1921 several experiments, having for their 
object the recovery of artificially stained moths liberated from a 
central point, had shown that the moths were capable of a total 
