265 



Imago. — Wings broad and short, generally oval in outline, with 

 long and dense surface hairs; entire body and legs with long hairs; 

 antennae with pedunculate joints, each joint with a whorl of hairs, 

 joints 12 to i6 in number; palpi 4-jointed. 



HABITS OF I^ARVAE; 



The larvae of Psychoda are found in cow dung, decaying vegetable 

 matter, exuding sap on tree-trunks, fungi, and in putrid water ; those 

 of Pcricoma are found in shallow slow-flowing water or in tree-holes; 

 Maurina has only been recorded from situations where the water had 

 a rather swift flow, and it is evidently adapted to this sort of habitat 

 by the presence of suckers on the ventral surface of the abdomen. 



The food of the larvae consists of algae and decaying vegetable 

 m.atter. 



HABITS OF IMAGINES 



The imagines may usually be found in large numbers in close 

 proximity to the larval pabulum, and are very common on windows 

 in outhouses or in houses that have damp cellars, or where there are 

 cesspools or cisterns. Rather dark, damp situations are particularly 

 favorable to the species in any stage. The flies may be found in great 

 numbers at lights at night. Many species of Pericoma are found upon 

 tree-trunks in the daytime. 



The food of the imago consists of nectar or fluid matter in the gen- 

 era Pcricoma and Psychoda, but the species of Phlehotomus are blood- 

 suckers, feeding upon the blood of various reptiles, amphibians, and 

 mammals — including man. Some species act as vectors of diseases 

 of man, papataci fever and verruga being transmitted by species of 

 Phlehotomus. Taylor has described a species from Australia, under 

 the name Pericoma toivnsznllensis^ , which he records as a blood- 

 sucker. It is not possible to decide as to the generic status of the 

 species, but his figure shows it to be either a Psychoda or a Phlehoto- 

 mus — probably it is the latter. 



Keys to Genera 



IjARVAE 



1. Ventral abdominal segments with median sucker-like disc ; thoracic 

 segments with larger chitinized plates than the following abdomi- 

 nal segments Maurinn (Pericoma) calif ornien sis. 



•Bull. Ent. Research, Vol. 1, Pt. 3, 1915, p. 267. 



