144 MISC. PUBLICATION 631, U. S. DEPT. OF AGRICULTURE 



such spots occur before the wing apex (at the ends of veins r u r 2 , r 4 , and some- 

 times r 3 ) and three behind (at the ends of veins m lt m 3 and cM 2 +2nd a). The an- 

 tenna (fig. 84, B) is 15-segmented, the thirteenth and fourteenth segments being 

 closely united to each other, and the fifteenth being smaller than either of the 

 two preceding ; the tip of the labium is not enlarged and is not provided with 

 teeth. Larva, (fig. So) : Larval characters are discussed by Johannsen (61, p. 

 21) and Malloch (85, p. 261) but at present they are too poorly known for any 

 to be considered as diagnostic. 



Geographical Distribution. — Nearctic Region : Quebec, Maine, New Hamp- 

 shire, Massachusetts, Rhode Island, Connecticut, New York, New Jersey, Penn- 

 sylvania, Maryland, District of Columbia.. Virginia, North Carolina, Georgia, 

 Florida, Tennessee, Ohio, Michigan, Illinois, Minnesota, Missouri, South Dakota, 

 Kansas, Texas, Montana. New Mexico, Washington. Oregon, California. Neo- 

 tropical Region : Puerto Rico, St. Vincent, Venezuela, British Guiana, Chile. 

 Palaearctic Region : England, France, Belgium, Italy, Malta, Norway, Sweden, 

 Finland, Denmark, Germany, Czechoslovakia, Austria, Hungary, Canary Is- 

 lands, Madeira, North Africa, Japan (?). Oriental Region: India, Philippine 

 Islands. Ethiopian Region : Gold Coast, Nigeria, Belgian Congo, South Africa, 

 Seychelles. Australian Region : New South Wales, New Guinea, Hawaiian 

 Islands. 



Biology and Pathogenesis. — The larvae may be found on the sur- 

 face film of foul water, in sewage, in the filter beds of sewage-disposal 

 plants, and in various types of wet, decaying organic matter; they are 

 frequently found in the traps of washbowls, and are capable of devel- 

 oping in water pipes. 



Eggs are laid in irregularly shaped masses of 20 to 100 or more. The 

 larvae hatch within 2 days ; their development is rapid. 



One case has been recorded of a girl in Japan vomiting living larvae 

 of "Psychoda b. punctata" ; this was probably intended for 6-punctata 

 (sexpunctata) , which is a synonym of this species. 



The Family SYLVICOLIDAE 



This family has been variously known as the Rhyphidae, Phry- 

 neidae, and Anisopodidae (Anisopidae). The antennae are 12- to 

 16-segmented, segments beyond the second not fused into a nagellum ; 



Figure 86. — Kylvicola fenestrates, wing. 



ocelli are present. Though related to the crane flies, the V-shaped 

 mesonotal suture that characterizes that group is absent in this family. 

 The wing venation is of a primitive type (fig. 86) ; in the more repre- 

 sentative members of the family the discal cell is present and the media 

 is 3-branched. 



The family has been treated in the "Genera Insectorum" by Edwards 

 and in Lindner's "Die Fliegen der Palaearktischen Region." 



