Animal Kingdom v.4

Page 128

22B INSECTA. rently with fewer articulations in the females. The proboscis is composed of a membranous, cylindrical tube, terminated by two lips forming a little button or inflation, and of a sucker consisting of five squamous threads which produces the effect of a sting. The wings are laid horizontally, one over the other, on the body, with little scales. The torment we experience from these Insects, particularly in the vicinity of low grounds and water, where they are most abundant, is well known. Thirsting for our blood, they pursue us everywhere, penetrate into our dwellings, particularly in the evening, announce their presence by a peculiarly sharp hum, and pierce our skin with the fine setre (dentated at the extt·emity) of their sucker; in propor­tion as they sink them into the flesh, the sheath bends towards the pectus and forms an elbow. They distil a venomous fluid into the wound, which is the cause of the irritation and swelling experienced ft·om their attacks. It has been remarked that we are only perse­cuted by the females. In America, where they are known by the names of Marangouins and Moustiques or Musquetoes, the inhabi­tants, as in other countries, defend themselves from them by sur­rounding their beds with gauze or a Mosquetoe-bar. The Laplanders remove them by fire and rubbing the exposed parts of their body with grease. These Insects also feed on the nectar of flowers. The female deposits her eggs on the surface of the water, and crossing her posterior legs near the anus, and slowly separating them as the ova are extruded, places them side by side in a perpen­dicular direction; the entire mass resembles a little bateau floating on that element. Each female lays about three hundred eggs in the course of the year. These Insects frequently survive the most in­tense cold. Their larvre swarm in the green and stagnant waters of ponds and ditches, particularly in sprirrg, the period at which those females lay their eggs who have passed through the winter. They suspend themselves on the surface of the water in order to respire, with their head downwards. They have a distin!tt rounded bead, furnishetl with two (species of) antennre and ciliated organs, by the motion of which they draw alimentary matters within their reach; a thorax with tufts of hairs; an almost cylindrical and elongated abdomen, much narrower than the anterior part of the body, divided into ten rings, of which the antepenultimate bears (above) the respi· ratory organ, and the last is terminated by radiating setre and ap­pendages. These larvre are very lively, swim with considerable velocity, and dive from time to time but soon return to the surface. After some changes of tegument, they then become nymphs, which still continue to move by means of their tail and its two tertninal DIPTERA. lins.. These ny mp h s a1 s o remain on th t: 229 a ~Ifferent position from that of the Ia e sur ac~ of the watet, but in bemg placed on the thorax· the ~vre, fthetr respiratory organs t' s m' h ' Y COnSISt 0 t b t e water also that the erfec I . wo tu ular horns. It form a sort of board ~ t nsect IS developed. Its ex . . or restmg pia h' uvtre swn. All these metamorph ce, ~ tch keeps it from submer-k oses occur 10 th wee s, and several generation e space of three or four year. s are produced in the course of the In the excellent work of M M . genus Culex of the preced' • eJgen on the Diptera of Europe the · . mg authors i d' 'd · ' spectes, m which the p l . f s lVl ed mto three. The · a P1 o the males 1 cts, and those of the female . are onger than the probos-s aJ e very short, form that of CULEX proper. c. . . ' • p~p1ena, L.; De Geer, Insect VI .. men annulated with br • . ''. ' xvu. Cinereous; abdo- Those in which the 1 .owfn, wmgs Immaculate(!). fi pa P1 0 the males are 1 orm another subgenus, as ong as the proboscis ANOPHELEs( 2 ). theT hose in which th ey are very short in both sexes compose a h , not er, ..E.nEs, Hoff.(3) M. Robineau Desvoidy, in his '' Ess . has added three others. at sur Ia tribu des Cuculides," The species in which the a) . . are shorter than the prob . p pt (labtal, according to his theor ) ta · oscts, and where th · Y rst are dilated and densely -~· e mtermediate tibire and the ge • c1 tated are de · n b • ~ertc appellation of SABETHEs( ) sig a~~d collectively by oscls ls elongated and 4 . Those, In which the sh t h recurved at the end d pro-or ' ave the first joint thickes 'an where the pal pi, also t, the other shortest' and th e t h ree ( 1) ~or the other species, see Mei . . Fr.~ Tlp?laires, P· 153. gen, Dlpt., I, 1; Macq., Dipt. du nord de Ia ( ) Ihld., I, 10; Macq. Ib'd 16 . (3) Ibid., 1, 13. ' 1 ., 2. (4) M~m. deJa Soc d'H' t . • ts • Nat. de Par., IIJ, 411.