IV. INSECTA: HEXAPODA, APHANIPTERA 



431 



Ncmocera in their long prol^oscis and in development. Tlie larvrc and pupaj 

 live in damp places or in water and move rapidly, the larvaj having biting mouth 

 parts. Black flies, Simuliid^e, excel the mosquitos in viciousness; the horse 

 flics, Tab,<\xid,e. Sub Order III. MUSCARI/E (Brachycera). Body short, 

 stout; antennee three-jointed with a bristle {arista) (fig. 485); legs short, ending 

 in an adhesive organ (puhnUiis); larva; headless, living in decaying substances 

 or parasitic in other animals. INIuscid^; house flies {Musca domestica* and 



Fig. 485. Fig. 486. 



Fig. 4S5. — Left, Erax haslardi, rubber fly; right, antenna of Muscid showing 

 arista at a. 



Fig. 486. — Caslrophilus equi* bot fly (from Hajek). /(, halteres. 



other species), blow fly (CalUphora voinitoria*), the flesh Hj (Sarcophaga car- 

 naria* viviparous) . i\Iany Muscida: convey disease, the house fly carrying the 

 germs of typhoid fever on its feet, while the tropical species of Clossina are 

 responsible for the nagana disease of cattle and horses and for the sleeping 

 sickness of man (p. 184). Asilid.e, robber flies (fig. 485) prey on other insects, 

 as do some Syrphid^: Eristalis* CEstrid^e, bot flies; the larvs alwavs 

 parasitic; those of the sheep bot {CEstrus ovis*) in the frontal sinuses of the 

 sheep, those of the ox warble {Hypoderma Imeata*) just beneath the skin of 

 cattle; those of Gasirophilus equi'''- (fig. 486), in the stomach of horse. In the 

 tropics Dermaiobia noxialis lives as a larva in the human skin. Sub Order IV. 

 PUPIPARA. Very active, often wingless forms living as parasites on mammals 

 and insects; larval development inside the mother; pupation occurring soon 

 after birth. Melophagus ovinus* sheep tick; Braula cceca,* bee louse. 



Order X. Aphaniptera (Siphonaptera). 

 In spite of the lack of wings the fleas are closely related to the Dip- 

 tera, since they have doubtless descended from winged forms, as they 

 have a holometabolous development. The larvie, 

 long and footless, live in decaying wood or dust 

 in cracks iii the floor, etc., and give rise to pupse, 

 both without traces of wings. Yet fleas and flies 

 differ in that fleas have similar body somites and 

 lack the haustellum, the suckiiag tube being formed 

 of labrum and mandibles, while the sharp maxilLx 

 puncture the skin. Besides Pidex irritans* the 

 flea that attacks man, many other species occur 

 on other animals. Fleas are now known to carry diseases, among them 

 the bubonic plague. In warm countries the jigger or chigoe, Sarcopsylla 



Pig. 487. — Pidcx irri- 

 tans^'^' flea (from Blan- 

 chard). 



