434 THE ANIMAL PARASITES OF MAN 



terrestrial and often dwell beneath the bark of decaying trees and even in 

 manure. They are cylindrical white grubs with the anterior part slightly 

 enlarged ; head small and retractile, segments deeply constricted, with 

 appendages on the pro thorax and on the anal segment. The pupae are 

 much shorter than the larvae and are broadest in front with two short lateral 

 appendages ; some have long filiform appendages on the back of the thorax. 

 This group of midges are known in America as " punkies." They are 

 most troublesome in the Tropics, but cause great annoyance by their bites 

 in many countries with temperate climates. Little or nothing is known of 

 the exotic species. 



Psychodidce, or Owl Midges. 



These small flies are easily told by their extremely hairy wings and 

 bodies and general moth-like appearance. The proboscis is usually short, 

 but in some exotic genera (Phlebotomus , &c.), it is elongated and horny, and 



FIG. 277. An Owl Midge, Phlebotomus, sp., greatly enlarged. 

 (From Giles' " Gnats or Mosquitoes.") 



these are vicious blood suckers. The larvae live in water, in rotting 

 vegetable substances ; they are more or less cylindrical with a short ter- 

 minal stigmatic tube. The pupae have . two long tube-like anterior stigmata. 

 The genus Phlebotomus occurs widely over tropical climes ; specimens 

 have been received by me from India, West and Central Africa and South 

 America. They frequently occur on windows in houses. F. V. T.] 



(b) Brachycera (Flies). 



The antennae as a rule have three joints, and are usually shorter than 

 the head. The first joint of the antennae is frequently very small, and 

 the third one is generally the largest, and sometimes possesses a terminal 

 annulated bristle. The palpi have from one to three joints; the mandibles 

 are covered by the labium. The three thoracic rings are coalesced ; 

 wings are almost always present, the posterior ones being rudimentary and 

 covered with a little scale. From the ova legless maggots are hatched, 

 which as a rule have not a distinct head, but occasionally possess two 



