standard value, and are indeed the materials which future formers or improvers of systems must necessarily employ in the construction of their edifices. They, as well as the specific characters, are written in Latin; and, after the example of Mr. Kirby, in his Monographia Apum Angliæ, miscellaneous observations are occasionally added in English. The following extracts will give equal information and entertainment to many of our readers who are not scientific naturalists.

"The purple emperor of the British oaks (papilio iris) is not undeservedly the greatest favourite of our English aurelians. In his manners likewise, as well as in the varying lustres of his purple plumes, he presents the strongest claims to their particular attention.

In the month of July he makes his appearance in the winged state, and invariably fixes his throne upon the summit of a lofty oak, from the utmost sprigs of which, on sunny days, he performs his aërial excursions; and it these ascends to a much greater élevation than any other insect I have ever seen, sometimes mounting higher than the eye can follow; especially if he happens to quarrel with another emperor, the monarch of some neighbouring oak: they never meet without a battle, flying upwards all the while, and combating with each other as much as possible; after which they will frequently return again to the identical sprigs from whence they ascended. The wings of this fine species are of a finer texture than those of any other in Britain, and more calculated for that gay and powerful fight which is so much admired by entomologists. The purple emperor commences his aerial movements from ten to twelve o'clock in the morning, but does not perform his loftier flights till noon, decreasing them after this hour, until he quite ceases to fly about four in the afternoon thus emulating the source of all his motions, the sun. The females, like those of many other species, are very rarely seen on the wing: the reason of which is both interesting and very little known. It is their being destitute of a certain spiral socket, which the males possess near the base of the main tendon of their upper wings; which socket receives and works a strong elastic spring, arising from the base of the under wings, thereby enabling them to perform a stronger, longer, and more easy flight than it is possible for the females to do. The males usually fly very high, and are only to be taken by a bag-net, fixed to the end of a rod, twenty or thirty feet long. There have been instances, though very rare, of their settling on the ground near puddles of water, and being taken there. When the purple emperor is within reach, no fly is more easily taken than him; for he is so very bold and fearless, that he will not move from his

settling place, till you quite push him off; you may even trip the ends of his wings and be suffered to strike again."

The observation on the bombyx quercus is no less curious.

don aurelians, when they breed a female of "It is a frequent practice with our Lon this and some other day-flying species, to take her whilst yet a virgin, into the vicinity of woods, where, if the weather is favourable, she never fails to attract a numerous train of the males, whose only business appears to be an incessant, rapid and undulating flight, in search after their unimpregnated females. One of which is no sooner perceived, tha they become so much enamoured of their fair and chaste relation, as absolutely to lose all kind of fear for their own personal safety, which at other times is effectually secured by the reiterated evolutions of their strong and rapid wings. So fearless indiced have I be held them become on these occasions, as te climb up and down the sides of the cage which contained the dear object of their eager pursuit; in exactly the same hurrying manner as honey-bees, which have lost themselves, climb up and down the glasses of a window.

"Whilst under this enervating fascination, if you even handle them, or suffer them to creep buzzing through your hands, they are not alarmed, as they would be at another time; but continue to urge ther pursuit as before; endeavouring to gain ad mittance into the cage. Of course any quanity of them may be readily taken and secured. In about four hours after the aurelians have thought proper to admit a male of their liking into the cage, to the poor drowsy ob ject of all this anxiety, she will not fail to deposit a great quantity of large impregnated eggs, of an oval shape, and whitish colour, blotched with darker marks; in miniature pretty much resembling those of a commer sparrow. The manners of this quiet captive female do not in any respect resemble those of her violent and restless partner; her disposition being sluggish and torpid in the extreme: she very rarely uses her wing, and appears much more inclined to repea than encourage the advances of her visher.

The aurelians call such a wedding as the above, a sembling (assembling) match, and never succeed with any but a virgin female! By what unknown and perhaps un named power the males distinguish between a married female, and one that has never been impregnated, I know not, and shock be glad to learn. But that they can and co make an unerring discrimination between the two, is well known to most aurelian They avoid the latter and never approach her; while for the former they display all the solicitude and anxiety I have above so fully explained. There was once an instance

of a male creeping into the pocket of an aurelian, which contained a virgin female in his pocket-box."

Lepidopterous insects are in general so conspicuous in point of size, and have been so greedily sought after by collectors on account of their beauty, that fewer indigenous nondescripts are likely to be found in this order than in any other of the class. A few however appear, especially in the last three sections of bombyx, for which there is no reference but to the author's Prodromus, or to the aurelian cabinet. The latter is a collection chiefly, as it seems, formed by Mr. Haworth, with the assistance of the members of the aurelian society, who are admitted into it on the express con

dition, that if they possess a collection, they shall give up at least one specimen of every species and variety which is not already in the aurelian cabinet, and for which they are to receive the fullest value, either in rare insects or in money. The society consists at present of ten members, who are all collectors of British insects, and every one of whom has contributed articles to the cabinet, which could not have been procured from any other source whatever. When the so ciety consists of twenty members, Mr. Haworth intends to give to them the whole cabinet, bonâ fide, and without fee or reward, to be kept by them and their successors, as a standard and permanent collection of British insects.

ACCURATE figures are of great advantage to the student in every branch of natural history. They do not, indeed, supersede the necessity, or diminish the value of clear technical description. This must always have a claim to primary regard, as without it there can be no true science. But though they can be admitted only in the humbler rank of auxiliaries, in this subordinate view the most experienced naturalist will not disdain their aid. They are not merely of use to identify, with less troubie, species which are discovered in dis tant countries, but convey many particulars to the eye which no language can express. Just definitions can explain to the understanding the general outline of a whole, with the relative situation and proportion of its parts; but they do it only by degrees, and, as they presert no distinct image to the mind, they casily escape from the memory. A skilful artist, on the other hand, effects his purpose by a single instantaneous impression : he gives at once the air, the character, and the spirit of the subjects which employ his pencil, introduces them to our knowledge in something like an embodied form, and enables us to recognise them as old acquaintance, whenever they fall under our actual observation.

In no part of natural history is the want of them more sensibly felt than in testaceology. The distinct parts of a

shell are so few and so simple; and, in many cases, not only kindred species, but even different genera diverge from each other by such minute and almost imperceptible gradations, that no terminology can be invented which will decisively discriminate one of them from another. Of the truth of this observation the discrepancies and doubts which perpetually occur in the works of the best writers on the subject, are an incontestible proof: nor can it be concealed, that, notwithstanding the assistance of good figures, every occasion of hesi tation is by no means entirely removed. Mr. Donovan, however, has done much to facilitate the investigation of this popular department of natural history, and has performed an acceptable service to the British conchologist, in giving coloured figures of our native species.

When he began to publish this work in numbers, he had calculated that all the British shells might be comprized in five volumes, or about 180 plates. But in its progress he found his materials so much increased upon his hands, by new acquisitions from various quarters, as to make it necessary for him either to extend his designed limits, or to exclude those species, which, from their extreme minuteness, are usually denominated mi croscopic shells. He has chosen the latter alternative, that he might not deviate from his original proposals to his subscribers; and offers the present vo

lume to the public with an assurance, that nothing of material consequence, either in his own collection, or the cabi. nets of his friends, has been omitted. It appears from several incidental passages in the work that he has had the good fortune to come into possession of Dacosta's collection, from which the British conchology of that author was formed: he has likewise had an opportunity to inspect many of the shells from which Mr. Pennant made his descriptions in the British Zoology, and has in consequence been able to detect several mistakes of both those writers in the application of synonyms. On this perplexing part of the science Mr. Donovan has bestowed much labour, and at the close of the work has candidly acknowledged, and desired his readers to correct an error into which he himself, in common with other British naturalists, had fallen with respect to the murex despectus and antiquus of Linnæus. The history of these species is so curious, and so clearly proves the rigid examination which ought to precede the quotation of any figure, that we shall lay it before our readers.

The murex costatus, figured by Mr. Pennant, in the frontispiece to his fourth volume, and again in a different position in the body of his work, is at present an unique in the collection formerly belong ing to the late duchess of Portland, and has been thought by some conchologists to be merely an accidental variety of what has been taken in England for the Linnæan murex antiquus. To justify the insertion of it as a distinct species Mr. Donovan thought it advisable to give an additional plate of what he also then thought murex antiquus, that the difference between the two shells may be more easily discriminated, though the claim of the latter to be received as a British species is rather dubious. But on a closer investigation of the subject he became convinced that the species bearing that name in several British authors is not the antiquus of Linnæus, but a species not known to him, which Mr. Donovan now calls .duplicatus, with the following specific character: "Shell patulous, tailed, oblong, the whorls light, tuberculated, striated with two raised ridges." The antiquus of Linnæus turns out to be what British authors have hitherto erroneously called despectus. Mr. Pennant's antiquus appears to be different from both. The account

of the real despectus we shall give in our author's own words.

"The present shell, it must be tacitly acknowledged, is inserted among the rarer shells of this country on very slight autho he once saw a few specimens of this murex rity; namely, that of a friend, who believes that were fished up in the sea at a short distance to the north of the Orkneys.-On this suspicion only we could not have presumed to insert the species in this work, were t not to avail ourselves of the opportunity afforded by that means to correct an error very generally admitted, concerning the true this time under consideration. murex despectus of Linnæus, the shell at

"To the English conchologist it need be scarcely said, that another shell, somewhat similar to the present, although specifically different, has been hitherto received as the murex despectus of Linnæus, by every wri ter in this country who has bad occasion to speak of that shell. The origin of this mistake, it will be perceived from the following entirely, with Linnæus himself. The murex particulars, rests in a great measure, if not despectus of this writer is noticed, for the first time, in the account of his travels through part of Sweden: a small octavo volume, written in the Swedish language, with notes, relative to natural history in Latin. At page 200, he describes this shell in these words, "cochlea spiris octo oblonga utrinque plate 8, fig. 5, of the some work, for a deliproducta lineis duabus elevatis," referring te neation of the shell; the figure quoted in every respect agrees with our specimen, not only in the general outline, but most exactly in having the slight carinated ridges that pass spirally round the whorls, a character not observable on the marex despectus of English authors. So far therefore we are condespectus of the Linnæan Iter Westroge vinced that the present shell is the mutex

thicum.

The work above mentioned appeared in 1746, the year in which Linnæus published the first edition of tus Fauna Suecica. In the latter, murex despectus is again described with a reference to his Iter W. Goth.; and in addition to that synonym, a shell figured by Lister, is also quoted for the same species. This is the source of that very confusion which has since arisen concerning the Lu Lister's Angl. t. 3, f. 1, is the reference given næan despectus, and should be fully stated by Linnæus. Adverting to this, we find the following definition of the shell given by

Lister, "bucciuum album læve nasimum septem spirarum."-He further adds, in the general description, "testæ pars exterior ex toto lævis est, i.e. sine striis quamvis sæpius vel rugis quibusdam vel aliis rebus extrilise and from the figure he has given of the shell, cus adnatis exasperetur." From this account, there is not the smallest reason to dispute that Lister means the shell which Englisk