512 



INSECTA. 



to vary its action, which is especially the case when they are seized or held in the hand. They live for a very long 

 time in a vacuum, or in different gases, except nitric, muriatic, and sulphuric acid gas, in which they die in a few 

 moments. Their immersion in hydrogen gas renders them, at least sometimes, detonating. When deprived by 

 mutilation of this luminous part of the body they survive, and this detached part preserves for some time its 

 luminous powers, either when submitted to the action of different gases, in vacuo, or in the open air, its phospho- 

 rescence depending upon its moistness rather than on the life of the animal, as it is easily re-lighted on moistening 

 the substance with watei ; it appears much more bright also when immersed in warm water, which is the only 

 fluid capable of dissolving it. 



These insects are nocturnal in their habits, the males being occasionally seen flying, like moths, round lights ; 

 whence we conclude that the luminous property of the females has for its object the attraction of individuals of 

 the other sex ; and if, as De Geer states, the larvae and pupae of the common Glow-worm are luminous, it is only 

 to be attributed to the developcment of this phosphoric substance from the earliest age. The males themselves 

 also possess this power, but in a very slight degree. Nearly all the species of hot climates have both sexes 

 winged, and as they occur in great quantities, they exhibit a brilliant spectacle to the inhabitants. 



Amydetet, Hoffrn., comprises some Brazilian species, having the antennas composed of more than eleven joints, 

 and strongly plumose. 



Phengodes, Hoffm., also consists of other South American species, with only eleven joints in the antennae, the 

 third and following joints emitting two long ciliated and curled filaments. 

 The remaining species compose the restricted genus 



Lampyris, divisible, from the form of the antennae, the presence or want of elytra and wings, &c, into many 

 minor groups. [See Laporte's revision of this genus in the Annals of the French Ent. Soc] 

 L. noctiluca, Linn., the male of which is nearly half-an-inch long, and has simple antennae ; a semicircular 



thorax entirely covering the head, with two transparent spots ; 

 belly black ; last segments of a pale yellow. The female is 

 destitute of wings and elytra, and is of a blackish colour; the 

 apex paler; the latter are more especially called Glow-worms. 

 They are found in the country, at the side of roads, in hedges, 

 amongst grass, &c, in the months of June, July, and August. 

 They lay a great number of eggs, which are large, spherical, 

 and of a citron colour. The larva nearly resembles the female, 

 but is black, with a pale spot at the hinder angles of the seg- 

 ments ; the antennae ami legs being much shorter, they crawl 

 slowly, and are able to shorten and lengthen their bodies. They 

 are probably carnivorous. 

 In our second division of the Lampyrides the antennas are 

 wide apart at the base ; the head is not formed into a muzzle, and the eyes are of the usual size in both sexes. 



Drilus, Oliv., has the antennae pectinated in the males, and shorter and subserrated in the females ; the maxil- 

 lary palpi are thickened towards the end, which is pointed. The males are alone winged, the female of the typical 

 species, D. flavescens, only recently discovered, being apterous, and nearly three times the size of the male. 

 M. Mielzinsky has lately observed the transformations of this species, the larva of which feeds upon the common 

 snail Helix nemoralis, Linn., and resembles that of a Glow-worm ; but the sides of the abdomen have a row of 

 conical tubercles, and two series of pencils of hairs. Not having traced the transformations of the other sex, 

 M. Mielzinsky regarded the female as forming a distinct genus, which he named Cochleoctoiius. 



All the other species belonging to this section or division of the Lampyrides are winged, and their maxillary 

 palpi are not much longer than the labial. 



Telephorus, Schaeff. ; Cantkaris, Linn., has the palpi terminated by a hatchet-shaped joint, and the thorax has 

 not lateral notches. The species are carnivorous, and crawl about on plants. Cantkaris fusca, Linn., is one of 

 the commonest species of this numerous group, [which are called Soldiers and Sailors by children]. Its larva is 

 subcylindric, elongated, soft, and of a velvety black colour ; the head is furnished with strong mandibles. Beneath 

 the terminal segment of the body is a fleshy tubercle, used in walking. It lives in damp earth, and feeds upon 

 prey. In certain years large spaces of ground in Sweden, covered with snow in the winter, have been observed 

 covered with great numbers of these larvae and other living insects, supposed to have been raised and transported 

 thither by violent gales of wind, whence the origin of insect rain, " pluie d'insectes." 

 Silis, Meg., has the thorax notched at the sides behind. «S. spinicollis, Charp. 



Malthinus, Latr., has the palpi terminated by an ovoid joint, and the elytra are shorter than the abdomen. The 

 species are very small, and are found upon plants. 



The third tribe of the Malacodermi, or the Melyrides, has the palpi generally filiform and short ; the 

 mandibles notched at the point ; the body generally long and narrow ; the head only covered at the 

 base bv a flat or slightly convex thorax, which is generally square or oblong ; the joints of the tarsi 

 are entire ; the ungues unidentate, or furnished with a membranous appendage. The antennas are 

 mostlv serrated or pectinated in some males. The majority are very agile, and are found upon leaves 

 of flowers. This tribe, which is only a dismemberment of the genera Canlharis and Dermestes, Linn., 

 composes that of Melyris, Fabr. 



Fig. 59.— Male ar.d female Glow-worm. 



