INSECTA. 345 
Corethra Mric. Antenne with fourteen joints in both sexes, 
with hairs verticillate, very long in male. Wings incumbent. 
Sp. Corethra plumicornis Mutc., Corethra lateralis Lavr., Panzer Deutschl. 
Ins., Heft 109, No, 16; Cuvinr R. Ani. éd. ill., Ins. Pl. 161, fig. 4; the 
larva lives in fresh water, has forward on the head two curved hooklets, 
and is very voracious ; R&éaumur Jns. v. Pl. 6, f. 4—1 5; SLABBER Na- 
twurk. Verlustig. Tab. 1. Iv.; Lyonnxt, Ouvrage post. Pl. 17, figs, 14, 
15, 19. 
Chironomus Mxtc., Tanypus ejusd. Wings deflected. Anterior 
feet remote from the rest, inserted almost beneath the head, very 
long (at rest porrect). Antenne filiform, with thirteen or fourteen 
joints in both sexes or in males alone, in females sexarticulate (Chi- 
ronomus MEIG.) 
Sp. Chironomus plumosus, Tipula plumosa L., Cuv. R. Ani. éd. ill., Ins. 
Pl. 161, fig. 5. The larva is a blood-red worm, often met with in rain 
reservoirs ; see RéaumuR Jns. v. Pl. 5, figs. 1-5. On the head are two 
black eye-spots, and two short antennz consisting of one joint and two 
threads at the point (these are wanting in R&auMUR’s figure). The head 
is alternately drawn into and pushed out of the next following joint by the 
larva. The eggs of Chironomus, oval or navicular and united in strings, 
were formerly taken for plants (Diatomacee): Gloinema AGARDH and 
Echinella ; see the observations of BERKELEY Ann. of Nat. Hist. vu. 1841, 
Pp. 449—451. Pl. xi. figs. 1—8; comp. KoELLiKer Observ. de prima 
Insect. genesi, 1842. 
B. Proboscis porrect, of the length of thorax, or longer than 
thorax, made up of seven sete. Palps quinquearticulate, porrect. 
Culex L. Antenne porrect, in male plumose, in female pilose. 
Wings squamate, incumbent. 
Hides HorrMANNSEGG. Palps in both sexes very short. 
Sp. dides cinereus HOFFMANN., Cuv. R. Ani. éd. il., Ins. Pl. 161, fig. 3. 
Culea Muic. Palps of male longer than proboscis, of female 
short, with first two joints very short. 
Sp. Culex pipiens L., ScHELLENBERG Tab. 41, Cuv. R. Ant. éd. ill., Ins. 
Pl. 161, fig. 1; everywhere very common, especially in the neighbourhood 
of turf-diggings, as in the province of Holland. The hum or song adds to 
the inconvenience. The females alone sting ; the males, known by their 
plumed antennz, little or not at all. Another species, with black-spotted 
wings and white-ringed feet, Culex annulatus Fasr., has been often met 
with by me here in Leyden in winter and in the first days of spring, in 
mild weather, in dwellings. 
The gnat (Cousin, Schnacke, Miicke) is commonly known. The larvze 
live in water, and hang on the surface to breathe, with head downwards. 
