ORDER vr. DIPTERA. 71 



The insects of this genus hve on garbage; the lai^ae have no feet, 

 they are cyhndrical and soft ; tliey feed on the roots of plants under 

 ^vhich they Uve ; the pupaj are motionless and cylindrical, with two 

 horns before, dentated behind. Some species live in the water, and 

 either swim or roll themselves up in a case. 

 Sp. 1. T. olcracea. {PI. 9. fg. 2.) 



Genus 72. MrscA. 

 Mouth with a fleshy exsertcd proboscis; two equal /yjs and a hamhUum 



furnished with seta% and two short jda//^/; ««/(,'/(««■ in most sj>ecies 



short. 

 Sp. 1. M. inanls. {PI. 9. fg. 3.) 



Genus 73. Tabakus. 



Mouth with a straight exserted membranaceous proboscis, ending in an 

 ovate capitulvim or knob; with two equal ///)>■; hunstcllum projecting, 

 exserted, and received into a groove in the back of the proboscis; 

 vagina univalve, with five seta and two equal pu/pi, the last articula- 

 tion of which is thicker than the rest ; antcnmc short, approximate, 

 cylindrical, \\ilh seven articulations; the third generally largest, and 

 armed with a lateral dent. 

 The insects of this genus suck the blood of animals. They are of a 



dull plain appearance, but their large eyes are in general beautifully 



coloured — these colours fade after they are dead. 



Sp. 1. T. tropicus. {PI. 9. Jig. 4.) 



Genus 74. Culex, ilic Gnat. 

 With an exserted, univalve, flexible ragiun; five .se/^; palpi two, con- 

 sisting of three articulations; anlciuiaiWifovni. 

 Sp. 1. C.pipieus. {Pt. 9. Jig. 5.) 

 Inhabits Europe and the northern parts of Asia and America. 



This insect is frequent in the neighbourhood of waters and marshy 

 places. In southern regions there is a larger species which is known 

 by the name of Musquetoe. Its bite is jiainfid, raising a considerate 

 degree of inflammation, and its continual piping note is exceedingly 

 irksome where it abounds, especially during the night. When it settles 

 to inflict the wound and draw the blood, it raises its hind pair of feet. 

 In Lapland, the injuries the inhabitants sustain from it are amply re- 

 paid by the vast numbers of water-fowl and wild-fowl which it attracts, 

 as it forms the favourite food of their young. 



Genus 75. Empis. 

 HausteUum inflected ; vagina univalve, with three sets and a proboscis ; 

 p«//)t short and filiform; antenna setaceous. 

 The changes of these insects are unknown; they are common on 



