COHETHRA. 251 



are articulated at the tip, and with two short palpi. The abdo- 

 men has a fan of hairs at the tip beneath. The pupa somewhat 

 like that of Culex, but straight, and with pointed thoracic ap- 

 pendages. 



" The larva of C. culiciformis much resembles that of Culex pi- 

 plens in form, but differs from it in its motions and station of 

 repose. Instead of being suspended at the surface with its head 

 downwards, it usually, like fishes, remains in a horizontal position 

 in the middle of the water. When it ascends to the surface it is 

 always by means of a few strokes of its tail, so that its motion is 

 not equable, but by starts. It descends again gradually by its 

 own weight, and regains its equilibrium by a single stroke of the 

 tail. Its anus is furnished with a pair of oars or natatory laminae, 

 by which it rises to the surface. The tracheae appear to proceed 

 from a pair of oblong vesicles of considerable size in the thorax, 

 and towards the anus they form two other smaller ones." 

 a. Tarsi not dotted. 



b. Antennae with brown bands. Species 1. 



b b. Antenna without bands. Species 2. 

 a a. Tarsi dotted. Species 3. 



1. plumicornis, P. E. S. iv. 246. 58 (1792); Meig. ; Mcq. ; 

 Guer. ; Zett. ; Gim. cristallina, D. G. lateralis, Latr. ; Panz. ; Lara. ; 

 Meig. Kl. Zw. hafniensis, Gmel. Mas et Fcem. fusca, antennis testaceis 



fusco-cinctis, thoracis vittis duabus lateralibus pectoreque albidis, alis 

 subcinereis, venis pedibusque testaceis, halteribus albis, abdomine pal- 

 lide fusco; Mas, antennarum plumis testaceis. Long. 3 ; alar. 5 lin. 



Brown. Antenna testaceous, with brown bands. Thorax with a 

 whitish stripe on each side. Pectus whitish. Wings slightly greyish ; 

 veins and borders thickly ciliated, the former testaceous. Halteres 

 white. Abdomen pale brown, hairy. Legs pale testaceous, pubescent. 

 Male. Plumes of the antennae testaceous. 



Generally distributed. (E. S. I.) 



2. culiciformis, ]). G. Iiis. iv. 144. 16. pi. 23. f. 3-5 (1783); 

 Latr. ; Lam. ; Meig. ; Mcq. ; Lehm. Mas et Fern, obscure fusca, an- 

 tennis niyris, thoracis lateribus pectoreque pallide testaceis, alis sub- 

 cinereis, venis pedibusque testaceis ; Mas, antennarum plumis nigris. 

 Long. 3 ; alar. 5 lin. 



Dark brown. Antenna black. Pectus and sides of the thorax pale 

 testaceous. Wings slightly greyish ; veins and borders thickly ciliated, 

 the former testaceous. Halteres white. Abdomen brown, hairy. Legs 

 testaceous, pubescent ; tibiae pilose. Male. Plumes of the antennae 

 black. 



Not generally common, but sometimes appearing in great pro- 

 fusion. (E. S. I.) 



