DIPTERA. 4.95 
10.) asserts that “la puce est un Diptére sans ailes.” Duges admits 
this relation, but considers the relation with the Hymenoptera* to be 
equally strong. The articulated sheath of the rostrum, as the labial 
palpi have been called, has been supposed to establish a relation with 
the suctorial Hemiptera}; but as this sheath is but a pair of articu- 
lated palpi, we must look elsewhere for the grounds of the relation, if 
it in fact exist. Whether the elongated exarticulate organs in the 
interior of the mouth can be considered as analogous (but merely from 
their action) to the setiform mandibles and maxillz of the Hemiptera, 
is, perhaps, questionable: beyond these I can perceive no further 
bond of union between the two orders; and the elongated maxillary 
palpi and the want of a labrum are characters quite at variance with 
those of the Hemiptera. 

— 

Orver DIPTERA Aristotle. 
(AntTLiata Fabricius; HALTERIPTERA Clairville.) 
Car. Wings two; mesothoracic, membranous, not capable of be- 
ing folded, with variable neuration, accompanied at the base by 
a pair of small alulets. 
* The transformations of this order agree with those of the flea; and an ana- 
logy may, by the exercise of considerable ingenuity, be traced between the parts of 
the mouth of the two orders ; but the flea has a suctorial, and the Hymenoptera a 
masticating mouth. (See Vol. I. p. 8.) 
+ Hence MacLeay (Hore Ent. p. 379.), adopting the views of Latreille (Hist. 
Nat. tom. xiv. p. 404.), places the flea between the Hemiptera and such Diptera as 
have the sheath of the rostrum bivalve but not articulated. Its nearest relations 
among the Diptera are, however, such species as have an incomplete pupa. Some 
of the fungivorous Tipulide, especially Cordyla, as suggested by Mr. Haliday 
(in Curtis, Ceratophyllus), make the closest approach. In their parasitic habits, 
however, they make a nearer approach to the Hippoboscide. 

$ Bretiocr. Rerer. ro THE DiereRA IN GENERAL. 
Schellenberg. Gattungen der Fleigen, 8vo. Zur. 1803. 
Herbst. Genre des Mouches Diptéres, 2 vols. 8vo. Zurich, 1802. 
Fabricius. Systema Antliatorum, 8vo. Brunsw. 1805. 
Fallen. Diptera Sueciz descripta, 2 vols. 4to. Lund. 1814-1827. —Ditto, Suppl. 
Dipt. Suec. Lund. 1826. 
Wiedemann, in his Zool. Magaz. vol. i. st. 1, 2, and 3. — Ditto, Nova Dipterorum 
Genera, 4to. Kiliw, 1820. — Ditto, Diptera Exotica, 8vo. Kiliz, 1821.— 
Ditto, Analecta Entomologica, <to. Kilia, 1824, — Ditto, Aussereuropaische 
zweifl. Ins., 2 vols. 8vo. 1828=1830. 
