MR. WESTWOOD'S INTRODUCTION TO THE MODERN CLASSIFICATION OF INSECTS.
THE object of this work is to fill up a middle station between the popular accounts of the curious habits and structure of insects, in such books as Insect Architecture, and the minutely anatomical and technical descriptions of more recondite publications ; the aim of
the author being, as he indicates, to supply a want psiliii:elohsaellbeenftoore- mological students have felt, who no sootier quit the generalized views of insect " wonders" presented by popular writers, titan they
of generic and specific descriptions. With this are plunged into the vast and to them the dry and repulsive details hint for the last sixteen years, Mr. 'WESTWOOD has studied the systems of different naturalists; he has examined and arranged the facts scattered throughout the voluminous transactions of tbreiga and native societies, and the various zoological and entomological magazines and other repertoria of science; he has also received much assistance from living naturalists and their collections; and he has " studied nature in the woods and fields, tending and oh- serving insects in all their various transformations." The plan of the work is thus described by its author—" I have commenced with general observations on insects, and then pro- ceeded to divide them into orders : I have afterwards taken up each order separately, dividing it into families, and giving an ac- count of the characters, habits, transformations, and general dis- tribution of the insects comprised within each family, with an illustration of their characteristic anatomical details and preparatory states." The descriptions are illustrated by wood- cuts, with magnified parts; tumbles of contents bring the leading masses of the subject under the eye at once ; an alphabetical index directs the student to the " ihmilies " he may be in search of; and an elaborate synopsis of British insects is added in the shape of' an appendix. Although of a larger grasp than books exclusively consisting of names, measurements, and anatomicel perticulars, the intregueues to the Modern Classification of insects is still, of necessity, so occu- pied with the science of its subject, that a full account of it would be of' no interest for general readers, and of no use to the ento- mologist. We Italy, however, glean a few extracts, to show that the author of the Entonedegist's 7'e:et-13eek omits no proper op- portunity of enlivening the dry thins by the living spirit.
HABITAT AND HABITS OF DYTICID.E.
The Dytichlte are found in all quarters of flue globe, inhabiting stagnant in prefl:rence to running waters. They swim with great agility, the hind-legs acting together in concert like those of a 11.0g, the anten11:c at the same time being ereeted, mid the palpi concealed. (Newman, in Ent. .31irg. vol. i. p 313.) They are very ' voracious in only other habits, attacking and devouring not n other aquatic insects but are also occasionally very destructive to young fish in lisp-pools (Vide ..1/ity. -Vat. Hist. NO 12.) Air. Anderson, the etuaiur of the Botanic t 1artlens, has also infmmed me that he has suffered much from these insects attacking young gold and silver fish, eating their dorsal and pectoral tins. Dr. Burmeister also mentions that a specimen of Cybister which he kept, devoured two frogs in the space of forty hours; end nevertheless, when be dissected it shortly afterwards, it was found to have entirely digested them, the intestinal tube being empty. They are very fearless in their attacks, seizing insects touch larger than themselves. A specimen of Dyt. marginalis, which Esper kept in water alive fur three years :11111 a hall; feeding, it with raw beef, is recorded by Clairville to have destroyed ,t specimen of the large hydrous picetts, (^1Ilt ui L twice its own size,) piercing it with its jaws on the only vulnerable point, viz. On the under side, at the pH, mion of the head in the thorax, and sighing its juices. Messrs. Kirby and ,,lice en- deavour to account for the extraordinary duration of life of tit, sptginten by supposing that it was cam, d by the cellbacy of the insect. (See 1/gg. Not. Hist. No. 1:4 fur observations out the tenacity of life exhibited by rlasse insects.) They employ their fore-L. ,7s Its claws in seizing and two eying their prey to the mouth ; and Dr. Illter okayed that his D. marginali: sd com- pletely sucked the blood out of the bits of meat with which he fed it, that they appeared only like small white mtt,tg4 llo.t thug in the water. Dr. Erichson, however, states that thtote winch it lei pt alixe refused to eat 11,,h, neither would they feed upon their compaoions am: ,s one happened to die; nod one, which De Geer kept, died in conselitete.tt of having eaten a hug.: leach which disagreed with it, large portions of it be:dq fliseh:irged the following day, un- digested, from the mouth. Atwording to i:::per and Erickson, they are, how- ever, able to fast for many weeks, am! even months ; butt if they lure kept out of water, they die in le very few days.
BEEE or -rite GNAT.
The extreme irritation produced by the bite of flue gnat is too well known even in our own country. The manner, however, in Nvhich. the operation is effected is into esting. Thirsting for its evening meal, the little animal enters our apartments, and instead of whirling, like the moths, round the light, it beftkes itself to its employment ; sounding an approach, however, by a tole- rably loud humming, which, in our chambers at least, is sufficient to banish sleep. Taking its station upon an uncovered part of the skin, with so light a motion as not to be perceptible when it alights, (although it will not hesitate to make its attacks occasionally through our thick clot 11 ing,) it lowers its rostrum and pierces the skin by means of its exceedingly slender needle-like lancet,, which are barbed at the tip:; and as by degrees it pushes these deeper into the skin, the lower lip or sheath, in which they were enclosed when at rest, becomes more and more elbowed towards the breast, until flue whole length of the lancets are introduced into the skin. It is supposed that at the same time it instils into the wound it VCBOBBILIS liquid, which, while it enables the blood to flow (luster, is the chief (mime of the subsequent irritation.
LABOUR or 'rate: bARVA: or 'r ua En BEETLES.
These larvae burrow cylindric retreats in the earth to the depth of a foot or more, employing their legs and jaws in loosening the particles of sand and earth, wl,Wh, they carry to the sortlive open their broad sauser-like head, as- cending by the assistance of the Imo hooks upon the back, setnewhat after the fashion of a sweep going up a chimney. Baring completed this burrow, they station themselroS, by means of their legs and dorsal hooks, at its mouth, thew large flattened head and first segment fitting the hole : her they Its in wait for such insects as may he crawling about, seizing them witfu their jaws, by suddenly throwiog the head b.wkwarut, and then dragging them to the bottom of the burrow where they may generally be found in -the position represented in fig. I, 7. At the least app1-00..:11 of danger they also immediately slide down to the bottom of their met rents.
Previous page
