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THE DIPTERA 



Tribe 2: Brachycera heterodactyla. — Orthorrhapha brachy- 

 cera with two or three pulvilH. In the last case the 

 middle is different from the two other pulvilli. Some 

 species without pulvilH. Posterior stigma of the larva 

 in front of the body-end. 



Families. — ^AsiHdse, Empidae. 



SUBORDER IL CYCLORRHAPHA. 



Definition. — Diptera with a lunula and usually a ptilinum. 

 Antenna with always three joints and an arista. Palpi one-jointed. 

 Mandibles absent. Maxillae rudimentary. Discoidal cell bounded 

 by the media and cubitus. Abdomen with seven segments at the 

 most, often with less. 



Section 1: Aschiza. — -Cyclorrhapha with a clearly defined lunula, 

 but a rudimentary ptilinum. Arista poorly developed. 



Families. — Not of interest in tropical medicine. 



Section 2: Schizophora.— Cyclorrhapha with lunula; at times 

 absent, but the arched suture over the antennae is well defined. 

 Ptilinum usually well developed. Antennae lie in separated hollows. 

 Arista well developed. 



Tribes : Muscidce acalyptratce and Muscidce calyptratce. 



SUBORDER III. PUPIPARA. 



Definition. — -Diptera with well-developed rudimentary or no wings ; 

 parasitic on vertebrates. The fully-developed larvae are passed 

 directly from the body of the imago without a free-living egg stage. 



SUBORDER ORTHORRHAPHA. 



SECTION NEMATOCERA. 



Family Culicid^. 



Definition. — Orthorrhapha nematocera with a long piercing pro- 

 boscis, and a body more or less clothed with scales and hairs. 

 Antennae with whorls of hairs or plumes, which may be dense and 

 long in the male, though scanty in the female. Wings with six to 

 seven longitudinal veins, with scales and two distinct fork cells. 

 The costa passes all round the wing, and carries scales, which form 

 a fringe. Metamorphosis complete. 



The Culicidae include the flies which we call mosquitoes, a word 

 which is derived from the Spanish, meaning little flies, and are the 

 same as gallinippers in America. The genus Culex was formed by 

 Linnaeus in 1790 for the gnat Culex pipiens ; the genus Anopheles, 

 from a Greek word meaning harmful, by Meigen in 1818; the genus 

 Stegomyia by Theobald in 1901. A great many other genera have 

 also been described, but are not so important in tropical medicine 



