CI ASS V. INSECTA. 289 



mat ion. He observed that the month contains the whole of the 

 usual parts which, mider various modifications, exist in all insects: 

 the mandibles are perfectly distinct from and unconnected with the 

 maxilhe: the maxillae are inserted behind, and somewhat below the 

 mandibles, whose base they conceal ; and the articulation of the 

 lal)rum is very evident from its semitransparency." Leach, Zool. 

 Misc. vol. iii. 



]Mr. Kirby, in the second volume of his Monographia Apum An- 

 gUa, gives the following account of Stj/lops Mcfitta : " Upon this in- 

 sect (^Mtlitta nigro-cEiieu) 1 discovered, last spring, a very singular 

 animal, which seems appropriated to the present germs. I had pre- 

 viously more than once observed upon other species something that 

 I took to be a kind oi Acurus,\\\\ic\\ appeared to be immovably fixed 

 just al the inosculations of the dorsal segments of the abdomen; at 

 length, finding three or four upon a specimen of Mclitta nigro-cenea, 

 I determined not to lose that opportunity of taking one off to ex- 

 amine and describe; but what was my astonishment when, upon 

 my attempting to disengage it with a pin, I drew forth from the 

 body of the Mclitta a white tleshy larva, a quarter of an inch in 

 length, the head of which I had mistaken for an Acarus ! After I 

 had examined one specimen, I attempted to extract a second ; and 

 the reader may imagine how greatly my astonishment was increased, 

 when, after I had drawn it out but a little way, I saw its skin burst, 

 and a head as black as ink, with large staring eyes and antennap, 

 consisting of two branches, break forth, and move itself briskly 

 from side to side. It looked like a little imp of darkness just emerg- 

 ing from the infernal regions. JNIy eagerness to set free from its 

 confinement this extraordinary animal may be easily conjectured. 

 Indeed I was impatient to become better acquainted with so singular 

 a creature. When it was completely disengaged, and I had secured 

 it from making its escape, I set myself to examine it as accurately 

 as possible ; and I found, after a careful inquiry, that I had not only 

 got a non-descript, but also an insect of a new genus, whose very 

 class seemed dubious." For further information on this Order I 

 must refer the reader to the eleventh volume of the Transactions rj' 

 the Linncun Society, Sowcrbj/'s British Miscellany, and Leach's Zoolo- 

 gical Miscellani/, vol. iii., all of which contain figures of the insects 

 of this Order. 



Order XV. DIPTERA. Linnt, Leach, Latr., ^c. 



Class Antliata. Fabr. 



The insects composing this Order are distinguished from all other 

 insects by the following characters. Wings two, naked, unprotected 

 Halteres (poisers or balancers) placed behind, and generally beneath 



