THE CANADIAN ENTOMOLOGIST 59 



paragraph, for the male. Later, notaljly on the evening of June 

 17, along the Chesapeake and Potomac Canal, only a few hundred 

 yards from where the first observations were made, females giving 

 this long flash, j^epeatedly came to electric lights operated in the 

 flashing manner of the main, when used both by the writer and by 

 Mr. H. S. Barber, the bulbs in both cases being shielded by a leaf. 

 The reverse attraction, as described in the foregoing paragraph, 

 was also observed at this time, and had previously been observed 

 by Mr. Barber and the writer, along t'le Canal on the evening of 

 June 3. There were, however, some curious exceptions: for in- 

 stance, on the evening of June 5, at the writer's residence, 1901 

 Jackson St., N. E., this city, an insect gi\ing the long flash was at- 

 tracted to a lamp giving the flashing light, and when captured 

 proved to be a male; also on the evening of June 13, at the same 

 place, using the electric lamp giving a long flash, two females and 

 four males were attracted, caught and identified. It was not found 

 necessary that either sex be flying to respond ; insects at rest on 

 leaves and fences repeatedly responded by flashing to stimulation 

 with the electric lamp, and would sometimes leave their locations 

 and fly to the light. Good results were never obtained unless the 

 light was either shielded with a leaf, or the bulb coated with a 

 solution of malachite green and chlorophyl in collodion. 



The third method of lighting observed for this species was that 

 already described as single, not very bright flashes, emitted at 

 intervals of a second or two while the insect is flying through the 

 air in almost any direction, dropping from a tree, or running around 

 on the ground or on the grass. In every instance these insects 

 were found to be females. Operating the electric light in imitation 

 of this flash did not seem to cause attraction of either sex, but in 

 one instance, when a male was obser\-ed on a fence rail, giving his 

 usual triple flash, and responding to the electric light flashes in 

 imitation of the usual long flash of the female, the change to the 

 type of flash above described caused him immediately to cease to 

 respond. Provisionally we may regard this as the flash of a 

 pregnant (or hungry) female. 



The fourth type of light-emission consists of a single, short, 

 bright flash, repeated at intervals of about four seconds or more. 

 This flash is the least common, and insects flashing thus were 



