654 EXPERIMENT STATION RECORD. 



ENTOMOLOGY. 



House flies, L. O. Howard ( U. S. Dept. Agr., Division of Entomology 



Girc. 55, 2. ser., pp. 8, figs. 6). — The difference between house flies and 

 several related species is briefly pointed out. The eggs, about 120 for 

 each individual, are usually laid upon horse manure. One-fourth 

 pound horse manure, taken from a pile of manure in August, contained 

 100 larv;e and 146 puparia. Larv<e are not found in perhaps the 

 greater part of ordinary horse-manure piles, but in one case about 200 

 puparia were found in less than 1 cu. in. of manure. 



" The periods of development were found to bo about as follows : Eggs from depo- 

 sition to hatching, one-third of a day; hatching of larva to first molt, 1 day; second 

 molt to pupation, 3 days; pupation to issuing of the adult, 5 days; total life round, 

 approximately, 10 days. There is thus abundance of time for the development of 

 12 or 13 generations in the climate of Washington every summer." 



Experiments were conducted during 1897 and 1898 to determine 

 whether a manure pile could be treated to stop the breeding of house 

 flies. 



"It was found to be perfectly impractical to use air-slaked lime, land plaster, or 

 gas lime with good results. Few or no larva} were killed by a thorough mixing of 

 the manure with any of these three substances. Chlorid of lime, however, was 

 found to be an excellent maggot killer. Where 1 lb. of chlorid of lime was mixed 

 Avith 8 qt. of horse manure 90 per cent of the maggots were killed in less than 21 

 hours. At the rate of a quarter of a pound of chlorid of lime to 8 qt. of manure, 

 however, the substance was found not to be sufficiently strong. [This, however, is 

 considered too expeusive for practical use.] It was found that 8 qt. of fresh horse 

 manure sprayed with 1 pt. of kerosene, which was afterwards washed down with 1 

 qt. of water, was thoroughly rid of living maggots. Every individual was killed by 

 the treatment." 



This remedy did not prove entirely satisfactory when employed on a 

 large scale. An attempt to prevent the breedingof house flies in a pile 

 of manure was begun early in April, 1898, and continued for some time. 



''While undoubtedly hundreds of thousauds of flies were destroyed in the course of 

 this work, it was found by the end of May that it was far from perfect, since used 

 at an economical rate the kerosene could not be made to penetrate throughout the 

 whole pile of manure, even when copiously washed down with water. A consider- 

 able portion of house-fly larvie escaped injury from this treatment, which at the 

 same time was found, even at an economical cost, to be laborious, and such a measure 

 in fact as almost no one could be induced to practically adopt." 



A measure which proved very successful was to place the manure 

 collected each morning in a closet, the window of which was provided 

 with a wire screen, and to scatter a small shovelful of chlorid of lime 

 over it. 



House ants, C. L. Marlatt (U. 8. Dept. Agr., Division of Ento- 

 mology Circ. 34, 2. ser., pp. 4, figs. 3). — The habits, life histories, and 

 characteristics of the red ant {Monomorium pharaonis) and the pave- 

 ment ant {Tetramorium ccespitum) are given and other species are noted. 



The possibility of driving ants away by the use of gum camphor is 



