538 JOURNAL OF ECONOMIC ENTOMOLOGY [Vol. 9 



10. Adults have been observed to emerge in an empty cage six feet 

 from a manure pile, the pupae having been produced by migrating 

 larvsp. The greatest larval migration was at least eight feet. 



11. In a naturally accumulated and infested manure pile larvae and 

 pupae were overwintered. Adults continued to emerge during mild 

 weather in mid-winter as long as manure was added. Emergence 

 stopped when addition of manure ceased, but in spring at least 142 

 adults emerged. 



References 



(1) BisHOPP, F. C, Dove, W. E., and Parman, D. C. 1915. Notes on certain 



points of economic importance in the biology of the house-fly. Journ. Econ. 

 Ent., vol. 8, No. 1, pp. 54-71. 



(2) Hutchison, R. H. 1916. Notes on the preoviposition period of the house fly. 



U. S. Dept. of Agr. Bui. No. 345. 



(3) Hutchison, R. H. 1914. The migi-atory habit of house-fly larva; as indicating 



a favorable remedial measure. U. S. Dept. of Agr. Bui. No. 14. 



(4) Hutchison, R. H. 1915. The maggot trap in practical use; and experiment 



in house-fly control. U. S. Dept. of Agr. Bui. No. 200. 



(5) Hewitt, C. G. 1915. Pupation and overwintering of the house-fly. Can. 



Ent., vol. XL VII, No. 3, pp. 73-78. 



SCIARA MAGGOTS INJURIOUS TO POTTED PLANTS 



By H. B. HuNGERFORD, University of Kansas 



During the winter months of 1912 numerous complaints were re- 

 ceived concerning a tiny black gnat that was appearing in annoying 

 numbers in conservatory windows and around the potted plants. In 

 nearly every case they were held accountable by the housewife for the 

 lack of thrift of many of her plants — an opinion not shared with any 

 degree of assurance by the writer. 



Upon investigation, the gnats invariably proved to be Myceto- 

 philid flies of the genus Sciara,^ and their shiny, black-headed white 

 maggots were to be found in the dirt of some of the potted plants — 

 sometimes in such numbers as to be turned out of the soil in small 

 squirming balls. 



Since this was the first time that these flies had been brought to our 

 attention in this relation, we were not only at a loss regarding means 

 of exterminating them, but, moreover, were skeptical as to the actual 

 damage they were doing, being more inclined to attribute the sickly 



^ Sdara coprophila. The writer is glad to acknowledge his indebtedness to Dr. 

 O. A. Johannsen of Cornell University for the identification of the flies and for placing 

 at his disposal bibUographical material. 



