420 ORDERS OF PTILOTA. 



De Geer we are indebted for our knowledge of the 

 transformations of many of these insects ; whilst Fabricius, 

 Latreille, Meigen, Fallen, Wiedemann, Robineau Desvoidy, 

 and Macquart, have successively established families, tribes, 

 genera, and species; the works of Meigen and Macquart 

 having especially contributed to this end. 



The following is the arrangement proposed by the latter 

 in his valuable " Histoire Naturelle des Dipteres," recently 

 pubhshed, and which I have adopted, with this variation 

 only, namely, that, with Latreille and Leach, I have con- 

 sidered the forest-flies as forming a primary section of the 

 order, whereas M. Macquart has placed them merely as a 

 family of the great group oi MuscidcB. 



Section L {Ovipara or Larvipara j Diptera, Leach.) — 

 Head distinct from the thorax; sucker inclosed in 

 a labial canal ; claws of the tarsi simple, or with one 

 tooth ; the transformation to the pupa state not taking 

 place within the body of the parent. 

 Division 1 (Nemocera). Antennse having six or more 

 distinct joints ; palpi with four or five joints. 

 Fam. 1 {Culicidce). Sucker with six lancets. 

 Fam. 2 {Tipulidce). Sucker with two lancets. 

 Division 2 (Brachocera). Antennae having three 

 distinct joints ; palpi with one or two joints. 

 Subdivision 1 (Hexachcsta). Sucker with six lancets. 



Fam. Tahmiidce, 

 Subdivision 2 (Te^racA^^a). Sucker with four lan- 

 cets. 



A. (Fam. CcenomyidcB, BeridcB, Stratiomyda.) 



B. (Fam. Mydasidce, AsilidcB, Hybotidce, EmpidcB, 

 HenopidcB, Nemestrinidce, Bomhyliidce, Anthra- 

 cid(E). 



C. (Fam. Therevid(e, Leptida, Dolichopida, Syr- 

 phidce.) 



