420 ORDERS OF PTILOTA. 



De Gcer we ore indebted for our knowledge of the 

 transformations of many of these insects; whilst Fabricius, 

 Latreille, Meigen, Fallen, Wiedemann, Robincau 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 " Ilistoire Naturelle des Dipteres," recently 

 published, and which I have adopted, with tlus 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 of Muscidte. 



SECTION I. (Ovipara or Larcipara; 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). Antennae having six or more 

 distinct joints ; palpi with four or five joints. 

 Fam. 1 (Culicidee). Sucker with six lancets. 

 Fam. 2 (Tipulida). Sucker with two lancets. 

 Division 2 (BRACHOCERA). Antennas having three 



distinct joints ; palpi with one or two joints. 

 Subdivision 1 (Hexachaeta). Sucker with six lancets. 



Fam. Tabanidee. 



Subdivision 2 (Tetracheetd). Sucker with four lan- 

 cets. 



A. (Fam. Ceenomyida, Beridee, Stratiomydee.) 



B. (Fam. Mydasida, Asilidee, Hybotidee, Emptd*, 

 Henopida, Nemestri*ida>, Bombyliida:, Anthni- 

 cida). 



C. (Fain. Therevidte, Leptida:, Dolichopidee, Syr- 

 pttfe.) 



