484 



INSECTA. 



-lulua, «itli tlie bod)' coiled i 

 u In.rit ol tli-r budy iinrollLd. w 

 itiiii-i magnified. 



friur principal rlivi^ions, ti.ilicrclerl at its siiin/iior edge, the two middle divisions Ijeinjj nan'ower and 

 shorter, and situated at tlie upper extremity of another piece, serving as a common hase ; the legs are 

 very short, and always tei'miiialed hy a single claw ; four legs situated immediately beneath the pre- 

 ceding piece of the form of the fullowiug, but placed nearer together at the base, v\'ith the basal joint 

 proportionately longer, and the majority of the remainder attached, in double pairs, to eaeli of the 

 succcedijig joints. The male organs are placed behind the seventh pair of legs, and tbo-e of the 

 female behind tlie second pair. The spiracles are placed alternately above the base of the feet, and of 

 a very small size. 



The Chilognatha crawl very slo\\ly, or, as we may rather say, glide along, rolling themselves into a 

 s]nre iir ball. The lirst segment of the body, and in some also tlie 

 second, is largest, ami represents a corselet, or small shield. It is on!y 

 at tlie fom'tli, tifth, or sixth segment in diiTerent species, that the dujjli- 

 eation of tlie legs enmmences ; the two or four first legs are entirely 

 free to the base, or they do not adhere to their respective segments but 

 by a middle or sternal line. The two or three terminal segments are 

 ; destitute of feet. We observe on each side of the body a series of pores, 

 which had been regarded as spiracles, but wiiich, according to M. Savi, 

 are merely orifices for the discliarge of an acid fluid of a disagreeable odour, which appears to ser\e 

 for the defence of these animals ; the respiratory apertures, discovered by him, are placed upon this 

 sternal piece of each segment, and communicate interiorly with a double series of pneujnatie pouches, 

 disposed in a- chain throughout the whole length of the body, whence extend traeheau braiielies whicli 

 are extended upon the utlier organs. According to JI. Sliauss, these vesicular trachcte are not cou- 

 m;cted together by a principal trachea, as is customary. 



The form of individuals just hatched is like a kidney, perfectly smoolh and without aiipendagcs ; 

 eighteen days afterwards they undergo a first moult, when they assume the adult shape, Imt tliry ha\e 

 only twenty -two segments, and the total number of their legs is twenty-six pairs. i\l. Sa\i appears 

 to contradict the assertion of De Geer, that the young have only three pairs of legs and eight rings 

 in the young individuals ; but is it certain that the moulting 

 (if which Savi speaks is really the first ? — or ought wc not, 

 on the contrary, to conclude that these young do not sud- 

 r!enlypass from a state exhibiting no locomotive organs to 

 one with so many as twenty-six pairs, or in ndier words, 

 tliat there are iutermeihate changes, which have escaped 

 tlic notice of M. Savi ? Do not the oliservations of the 

 Suedisb Reaumur confirm these intermediate eliaii: 

 alone serve for loconioti(jn. At the second moulting the animal exhiliits thirty-six jiairs, and at 

 the third moult I'orty-three ; at this time the body consists of thirty segments. In the adult state ihe 

 Biale has thirty-nine, and the female sixty-fnur ; two years afterwards they again moult, at which period 

 the generative organs first appear. From their birth, which takes place in , March, until Xovcndier, 

 when Savi ceased his observations, tliese changes of ihe skin took place nearly monthly. In the 

 exuvia;, even the membrane wliieb hues tlie interior of the elciiientaiy canal and traclie;c is to be 

 jicrceived, the organs of the mouth being the only jiarts which jM. Savi could not discover. 

 ( O-^fiervaz/oni pfr sertyrt' nlla aior'ta di una ifpecie di Iitluii commuitl^fshna, Bologna, 1817 ; and another 

 memoir upon /»/«« /",e//(/K,v!iHff, pnblished in 1819, noticed in Vat Bulletin ofFervssac, December, 1823). 

 These inseets feed ii|ioii decaying animal and vegetable matter, and they deposit a great number of 

 eggs under ground. Aceordjiig to Linnasus they form the single genus 



luLUS, Linn., — 



which we divide as follows : — 



Some have the body crustaccous, without aiipcndages at the tip, and the antenna; thickened towards 



tlie extremity. 

 [Fam. I.— Glomerid-E, \Yestw., or the Oni.ui/'irmex of Latrrillc, in the Cmrs ,r Eiito,iin!o,,ir.] 

 Glomeris, Latr., resembles Wood-lur, ln-ing of an ov.il f.irui, ami rnllm- llauisrlves into a hall; the lioily 



convex ahove, concave heneath, witli a row of siiiiill srnles i'lnng einh sulc of tlie limly hciii:illi, analogous to 



iMi li of tlie lateral divisions of the TiiloOUes. Tlu'V' arc only composed of twelve segments, exclusive of the 



;. 4.T — Trnnsf.-iriiiatioiis of Juhis, from Oe Gcer. 



He this as it may, the eighteen outer legs 



