HOW TO KNOW THE IMMATURE INSECTS 



ORDER DIPTERA 

 Key to the LARVAE of the more important families 



(After John R. Malloch, 1917) 



la. Mandibles moving horizontally; head complete, 

 ii not, the posterior portion with deep longi- 

 tudinal incisions, or the thorax and abdomen 

 together consisting of 13 segments. Fig. 531. 



Suborder ORTHORRHAPHA, 



series NEMATOCERA 3 F.g. 531. Head of 



Cuiex sp. 



lb. Mandibles moving vertically; head incomplete, 

 without a strongly developed upper arcuate plate. 

 Fig. 532 2 



.-£S 



Fig. 532. Anter- 

 ior part of body, 

 showing the man- 

 dibles. 



2a. 



2b. 



Maxillae well developed, palpi distinct; mandibles 

 normally sickle-like; antennae well developed on 

 the upper surface of a slightly arcuate sclerotized 

 dorsal plate. Fig. 533. 

 Suborder ORTHORRHAPHA, 



series BRACHYCERA 16 



Fig. 533. Dor- 

 sal aspect of 

 head. 



Maxillae poorly developed, palpi visible only in a few larvae: 

 mandibles short and hook-like; antennae poorly developed or 

 absent, when present situated upon a membranous surface. 

 Fig. 534 Suborder CYCLORRHAPHA^ 



rv 



Fig. 534. a, Drosophila melanogaster Meigen (Calif. Exp. Sta.); b, Hes- 

 sian fly, Phytophaga destructor (Soy) (U.S.D.A.); c, Eris- 

 talis bastard! Macq.; d, Toxomerus politus Soy; e, Leucopis 

 Sriseora Fall (U.S.D.A.); f, Common cattle grub, Hypoderma 

 lineotum De Vill) in host sk\n (U.S.D.A.); g; Mediterranean 

 fruit fly, Ceratitis capitata (Wied.) with an anterior respira- 

 tory organ (Calif. Exp. Sta.). 



■^Key to families is not available. 



189 



