46 



BULLETIN 67, UNITED STATES NATIONAL MUSEUM. 



insects will alight upon it. Other insects, especially beetles, have 

 the tendency to fly at the light and then fall. A tapering bag placed 

 below the light, with the bottom opening into a cyanide jar, will 

 secure these. 



Many collectors have devised various forms of traps to capture 

 the insects that come to the light. One (fig. 87) is by Professor 

 Gillette. It is. in three parts, all of bright tin. The funnel is 22 

 inches in diameter, the tube 2J inches. This tube fits into the top 

 of the reservoir below; the latter has a removable bottom. The 

 reservoir is nearly filled with loose excelsior. The bottom is re- 

 moved, and in its place is put a wide-mouthed glass bottle half full 



of cyanide. The cyanide should be 

 slightly moistened and a piece of paper 

 or wire . mesh placed over it. The ap- 

 paiatus can be suspended in a tree or 

 placed on a stand, and a large lantern 

 hung over the top of the funnel so that 

 the blaze will be just above the top of 

 the funnel. It is well, on good nights, 

 to empty the reservoir before leaving 

 it for the night. This is done by tak- 

 ing out the excelsior and insects, plac- 

 ing them in cyanide bottles, and put- 

 ting new excelsior in the reservoir. 



The apparatus used by Mr. Morse is 

 described by Mr. Smith as follows: It 

 consists of a box of wood, having glass 

 on each of its four sides and a cover 

 with arrangement for outlet of heat and 

 smoke similar to old-style street lan- 

 terns. At the bottom are holes for 

 the ingress of air. The box is large 

 enough to contain . an ordinary kero- 

 sene lamp with chimney and is supported over a wooden box 

 about 18 inches square, which in turn contains a zinc pan about 2 

 inches deep and as large as will go into the box. At the base of each 

 pane of glass is a slot the whole width of the glass and about 1 inch 

 wide, which opens directly into the pan below. The pan is filled 

 about half full with water and then about a pint of kerosene is 

 poured on top. The moth strikes the glass and falls through the 

 slot and is killed by the oil. In the morning he takes a good-sized 

 pasteboard box, in the bottom of which is about a dozen thicknesses 

 of old newspaper and with a slender pair of forceps picks the moths 

 out by the legs and lays them on the paper. They are left there 

 for about two hours to get rid of most of the oil and water; then 



Fig. 87. 



SirvS. 



-The Gillette trap light. 



