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Show IUO DE J ANETRO· 34 May-June, 1832. . h. When several were water and sends forth a pleasmg c di~~· nt notes. Various ' . harmony on lllere l together they sung m t' kept up a cease css . k t at the same Ime, cicadre and cnc e. s, d b the distance, was not un- . b t hiCh softene Y t shnll cry, u w ' . f d 1{ this great concer com- E vemn()' a ter ar Pleasant. very e o 1' t 'nO' to it until my atten-d ft have I sat IS em o ' menced ; an o en b some curious passing insect. tion has been drawn away .Y * flitting about from . the fireflies are seen f At these times I ht belon()'ed to the family o h d All that caug o hedge to e ge. d the greater number were 'd or glowworms, an . d th Lampyn re, . . I found that this insect emitte e Lampyris occ'tdentalzs. . . d . . the intervals the ab- 'll' t fl. hes when uritate · m most bn Ian as d The flash was almost co- . 1 · were obscure · domma rmgs . b t it was first just percep- . · the two rmgs, u · d mstantaneous m . The shining matter was flmd an tible in the anter~or one. h the skin had been torn, very adhesive: httle spots~ w er~ till t' whilst the unin- . h · th a shght scm a wn, continued bng t WI d Wh the insect was decapitated · d t were obscure · en 'll' JUTe par s . . tedl bright, but not so bn Iant the rings remamed unmterrup y . d the 1 . . t t' with a needle always mcrease a~ ~efore : loc~ lf~I ~:.on The rings in one instance retained vividness of t e g 1 twenty-four hours after the their lumi~o~s pr~per;;.o:a;h~se facts it would appear prodeath of t e hmsec .' al has only the power of concealing or bable that t e amm d h t t ther . ' . h' the light for short intervals, an t a a o extmgms mg 0 th ddy and wet times the display is involuntary. . n e ~~ num-avel- walks I found the larvre of this lampyns m grea~ gr h . bled in general form the female of the Enghers. t ey resem f bl 1 . ous . .1 These larvre possessed but ee e umm hsh g owworm. h li ht t ers. ve differently from their parents, on t e ~ ~ .es po:h they Zgned death, and ceased to shine ; nor did .untattoioun exci' te any fr·esh display · I kept several of them ahve for d k . ht the light could be seen at about two hundred paces • On a ~r mg k bl that in all the glowworms, shining elaters, and d. tant It IS remar a e l t a IS • • • 1 h' h I have observed (such as t te crus ace , • US marme amma S, W IC ) h l" ht vmaendou sre, nere1'd .....,. , a coralline of the genus Clytia, and Pyrosoma , t e lg has been of a well-marked green colour. May-June, 1832. GLOWWORMS. 35 some time : their tails are very singular organs, for they act, by a well-fitted contrivance, as suckers, or organs of attachment, and likewise as reservoirs for saliva, or some such fluid. I repeatedly fed them on raw .meat; and I invariably observed, that every now and then the extremity of the tail was applied to the mouth, and a drop of fluid exuded on the meat, which was then in the act of being consumed. The tail, notwithstanding so much practice, does not seem to be able to find its way to the mouth; at least the neck was always touched first, and apparently as a guide. When we were at Bahia, an elater ( Pyropltorus luminosus, Illig.) seemed the most common luminous insect. The light in this case was also rendered more brilliant by irritation. I amused myself one day by observing the springing powers of this insect, which have not,* as it appears to me, been properly described. The elater, when placed on its back and preparing to spring, moved its head and thorax backwards, so that the pectoral spine was drawn out, and rested on the edge of its sheath. The same backward movement being continued, the spine, by the full action of the muscles, was bent like a spring ; and the insect at this moment rested on the extremity of its head and elytra. The effort being sudden1y relaxed, the head and thorax flew up, and, in consequence, the base of the elytra struck the supporting surface with such force, that the insect by the reaction was jerked upwards to the height of one or two inches. The projecting points of the thorax, and the sheath of the spine, served to steady the whole body during the spring. In the descriptions which I have read, sufficient stress does not appear to have been laid on the elasticity of the spine: so sudden a spring could not be the resu]t of simple muscular contraction, without the aid of some mechanical contrivance. On several occasions I enjoyed some short but most pleasant excursions in the neighbouring country. One day * Kil'hy's Entomology, vol. ii ., p. :JI7. D2 |