24 



JOURNAL OF ECONOMIC ENTOMOLOGY 



[Vol. 3 



OBSERVATIONS ON THE HOUSE-FLY 



By B. P. Felt, Albany, N. Y. 



An attempt was made the past season to obtain accurate data 

 respecting this insect's behavior toward light. The principal object 

 of the experiment was to determine the possibility of storing manure 

 and other substances in which this pest breeds, in dark or nearly dark 

 cellars or compartments. 



Outline of Conditions. A fly vivarium was located in the writer's 

 back yard (a typical village lot) at Nassau, Rensselaer County, N. Y. 

 This building was a nearly light-proof structure 6 x 10 feet in outside 

 dimensions and with a height of 6 feet 4 inches in front and 5 feet 6 

 inches in the back. To facilitate the location of materials, etc., the 

 spaces between the joists were numbered consecutively, beginning at 



Fig. 1. Plan of fly vivarium (original). 



the door on the north wall and running around and including in the 

 enumeration the spaces of the partitions as well as the outside wall 

 (Fig. 1). A light-proof window (18x18 inches) was made in the 

 south wall near the southwest corner (at station 16) and another in 

 the west wall (at station 13). Light-proof partitions, arranged some- 

 what like those in a photographer's dark room, divided the interior 

 (Fig. 1) in such a manner that there was a constant decrease in the 

 light as one progressed from the door back through the partitions and 

 around to the darkest corner near the middle of the south end (station 

 12). Ventilators w^ere provided in the roof at A and B (Fig. 1). 

 There is in the southeast comer, at station 23, a small closet 21 inches 

 deep and 3 feet above the ground. The interior of the building was 

 painted a dull black the latter part of April. The door located at the 



