582 HOWARD 



with semi-transparent abdomen seen at such times on windows. 

 This species is known in German}'- as the little house fly 

 (' Kleine Stubenfliege '). The larvae are said by Schiner to live 

 in decaying vegetable material. Heeger states that he reared 

 it from larvee found in the larvae of Epischnia ca^iella^ a lepi- 

 dopterous insect, and Roth found them in the nests of the com- 

 mon bumble-bee, Bombus terrestris, Hagen (Proc. Bost. Soc. 

 N. H., XX, 107) reports a case in which a larva, presumably 

 of this species, was found in the urethra of a patient. (Prob- 

 ably a case of pseudoparasitism.) 



At Washington, one specimen issued on the 25th of May from 

 human excreta gathered on the 12th of May, and the adult was 

 also captured upon the same deposit before it was placed in the 

 breeding cage. It was also reared on the 26th and 27th of June 

 from miscellaneous material collected on the 13th. At Travilah, 

 Maryland, it was captured upon exposed faeces June 15, 1899, 

 and was also captured during the same month at Twining City, 

 Maryland. Six specimens issued in January from excrement 

 taken in a privy in Alexandria in October, 1899. 



Homalofnyta scalaris Fabr. 

 This species, also common to Europe and North America, is 

 said to live, in Europe, in the larval state, in dry, human excre- 

 ment. It was reared at Washington in a single instance on May 

 24 from faeces collected on the 12th. 



Limnophora arcuata Stein. 

 The metamorphoses of the flies of this genus are not known. 

 This species has been captured on excrement and bred from 

 the same substance at Washington and at Travilah, Maryland, 

 and was also captured upon excrement in Porto Rico by Mr. 

 Busck. From excrement deposited May 12 and exposed six 

 hours adults issued June 16. On May 16 adults were almost 

 immediately attracted to a fresh deposit. The adult is a small 

 fly varying in color from gra^'ish to nearly black. 



Ophyj-a Icucostoma Wied. 

 The larva of one European species of this genus, probably 

 the species under consideration, is said by Schiner to live in 



