have kept some years in captivity, from weakness, never underwent a moult the first season, but retained its feathers until the following autumn, when they were renewed freely. This shows that their natural shedding is dependent on a periodical condition of the bird, and is, moreover, incompatible with a weakly state; though, in the latter case, we have already seen that, in instances where the new plumage would have been of a diverse hue, as in the shoveller before mentioned, the retained feathers become tinged with the colouring secretions, as is likewise observed even when they are about to be replaced. The tendency to cast the feathers would thus seem to be a connected sequence of the elaboration of these secretions, but requiring a more vigorous state of the constitution to promote its effectuation: the implied dependency, however, will appear unreal as we proceed.

Here it may be inferred, that, when a bird is moderately vigorous, its seasonal change of tint may be partly induced in both ways; many of the old feathers being retained, but altered in tint, to correspond with those newly put forth for it may be noticed, that as the disposition to change feathers continues only for a certain period, during which it is so strong, in a healthy individual, that I have even known those which had been accidentally lost and renewed but a few weeks previously, to be again shed and replaced by others at the regular moulting time; so, on the other hand, as in the instance mentioned of the caged snowfleck, and as I have also had occasion to observe in other cases, when this season of natural renovation has passed by, and a bird had been too weakly to renew its feathers then more than in part, the remainder have been invariably retained till the next moulting period, however distant.

(To be continued.)

REVIEWS.

ART. I. The Naturalist; illustrative of the Animal, Vegetable, and Mineral Kingdoms. Edited by Neville Wood, Esq., joint Editor of the " Analyst," Author of "British Song Birds," &c. No. 7. Vol. II. London: Groombridge.

THE late conductors of the Naturalist, Messrs. Holl and Maund, having found it expedient to resign the editorship of that publication, its continuation has been undertaken by Neville Wood, Esq., of ornithological celebrity; distin guished more for the zeal and enthusiasm which he has displayed in pursuing that department of zoology, than for the

benefit science has derived from the record of his observations.

On the first appearance of this periodical, we did not think its contents calculated to affect, in any material degree, the march of enquiry into either the animal, vegetable, or mineral kingdom; and when, a short time since, a prospectus fell into our hands, announcing a change in the editorial arrangements, the perusal of that document by no means impressed us with favourable anticipations of future improvement. Puffing, in any shape, we have an utter aversion to; but, in matters professedly connected with the advancement of science, the slightest indication of it cannot be too carefully avoided; and though, owing to the credulity of some classes of our countrymen, a tradesman may find it answer his purpose to advertise his goods as fifty per cent better than those of his neighbours, yet we doubt whether the employment of similar means on the part of either editors or proprietors has a tendency to increase the respectability, or promote the circulation, of a scientific journal.

"The proprietors of the Naturalist beg to return their sincere acknowledgments to the public for the very favourable reception it has been pleased to give this periodical." The "proprietors" farther state, "It may be affirmed, without fear of contradiction, that in no other monthly publication on the subject will be found half so much or such various intelligence as in the Naturalist, at the same price." Had not our copy of the above been forwarded through the proper authorities, we should certainly have supposed that some wag had been playing off a joke at the expense of the "proprietors" and "eminent scientific men" by whose assistance the Naturalist was to have been carried on. So favourable was the reception given by the public to this periodical, that it was discontinued after six numbers had appeared; and the scientific world would, probably, never have been in possession of the seventh, but for the enterprising spirit of Mr. Neville Wood. How far the keeping the public in a state of suspense during two or three months was a proper return for favours received, is a point that, perhaps, we ought not to venture an opinion upon; but the "proprietors" very judiciously observe, in their notice to correspondents, that "this delay has enabled them to effect various important improvements in, and additions to, the work; and, as they promise, if liberally supported, to continue the publication regularly, they trust the omission will be forgiven." These alterations, seven in number, have been approved by several individuals eminent in natural science. The first is the omission of the coloured

frontispiece; and the last, by far the most important of all, an intimation that "the papers admitted will be of a more practically interesting and useful character than heretofore: and fairness and impartiality may always be relied on by authors appearing before the critical tribunal of the Naturalist." The former conductors will, doubtless, fully appreciate the compliment thus paid to them, in their editorial capacity, by the "proprietors," in framing this seventh alteration. After, however, the notice which appeard in the Naturalist of "British Song Birds," we own that some hint about future impartiality in the reviewing department was by no means impolitic. We certainly felt, when perusing that critique, rather puzzled to comprehend why the reviewer should so "deeply marvel," and express such profound astonishment, at a production which, from a casual acquaintance, appeared to us not to indicate anything more than that its author possessed, in common with a host of others, the power of observing the habits of birds, and of committing those observations to paper. The article forcibly brought to our recollection a passage in the first number of the Naturalist, where Mr. Mudie speaks of those ages in which "single scintillations" were regarded as "stars of the first magnitude, after which the benighted children of men wondered and worshipped." Shortly, however, after Mr. Neville Wood's prodigious attainments had been thus blazoned forth in the Naturalist, his name appeared, in conjunction with the editor of that periodical, as joint editor of the Analyst !

We must turn, however, to the number before us, being the seventh from the commencement, and the first of the second volume; and here we have great satisfaction in observing that its contents fully justify the promise, held out in the prospectus, of an improvement in the general matter and tendency of the articles admitted. The communications have not that artificial character with which many of those appearing in the early numbers were invested; and we do not remark one that deserves to be spoken of otherwise than in terms of commendation.

The subjects introduced are, first, a paper on the Lemùridæ. The writer treats of the general habits and characters of the Lèmur family, and its relations to allied groups, which are pointed out in a clear and interesting manner. The genera Lèmur, I'ndris, Propithècus, Galeopithècus, and Cheirogàleus are described in detail; and the subject is to be continued in a future number. The author's name is not given; but his remarks seem founded on personal observation, and indicate

considerable practical acquaintance with the family which he describes.

Description of the Muscular Apparatus of the Wings of Birds. By William Macgillivray, M.A., &c. This is principally a paper of anatomical detail; giving the origin, insertion, and action of each of the various muscles brought into operation during the flight of birds. Mr. Macgillivray remarks that "The flight of birds has not been hitherto described, further than in the vague and general manner in which it is treated in anatomical works, and in the descriptions of ornithologists. It exhibits, however, a vast variety of modifications, some of which I shall endeavour to describe in a further communication, to which the present will answer as a basis." This, and the preceding paper, are illustrated with woodcuts.

Notes on the Amàræ, by Peter Rylands, Esq., contains some very useful suggestions.

An explanation of the Latin names of British Birds, by the Rev. F. O. Morris, B.A., and a Catalogue of the poisonous Plants found in the Neighbourhood of York. (Anon.)

Sense of Smell in Carrion Birds, by the Rev. F. O. Morris, B.A. Mr. Morris relates a fact of some crows discovering a carcass buried under a deep fall of snow. He remarks, "I have read the discussion carried on on this subject by Mr. Waterton in Loudon's Magazine of Natural History. I was always of opinion that Mr. Waterton was right; and I am now confirmed in that opinion. Certainly, in the case in question, the crows must have been directed to their food by the sense of smell alone, no part of the carcass being visible to the sight."

Habits of the Fitchet Weasel (Mustèla putòrius Linn.) This is an interesting notice. The writer states that he has examined many holes of this animal, but has never yet met with anything to confirm the fact related by Bewick, of its preying upon fish.

The contributors of short communications are, Edward Blyth, Thomas Allis, J. D. Salmon, the Editor, James Stuart Menteath, P. J. Selby.

ART. II. Conchological Illustrations; or coloured Figures of all the hitherto unfigured Recent Shells. By G. B. Sowerby, jun. Published by G. B. Sowerby, Sen. 50. Great Russell Street, Bloomsbury.

We have been much pleased with the examination of this well-executed and highly useful publication; and, upon

making some enquiries respecting its origin and progress, the result is highly creditable to the industry and ability of its conductor.

It appears that the arrival of Hugh Cuming, Esq., into this country, with large accessions to the then known species of shells, gave rise to the first idea of establishing an illustrative work, to make them known to the public; and, as new species are continually occurring, while many other species, which, although known, have not been correctly figured, the work was not likely to be soon at a stand for want of subjects. It was commenced in October, 1832; between which and the present time 118 parts have been published. These, as we learn from a notice on the wrappers, contain about 975 figures of about 678 species and varieties belonging to 15 genera.

Mr. G. B. Sowerby, sen., has considerably increased the value the work, by inserting in it, from time to time, complete catalogues of several genera, containing references to figures of each species in this or some other conchological work, with descriptions of those species which have not been previously characterised. Catalogues of the genera Cypræ`a Cancellaria, Nùcula, Amphidésma, Ebúrna, Èùlima and Fissurélla have already appeared; and, from the careful manner in which they are compiled, as well as from the eminence of their author, promise to be extremely useful.

Although we understand, from the titlepage, that the work is intended only to illustrate such species as have not been figured elsewhere, yet it seems that this rule has, in two or three instances, been departed from: for instance, the genus Cypræ a, the new species of which occupied the first 8 parts, is now being continued from Part 101., in order to give the whole of the species, whether published before or not; thus forming a monograph of the genus. Such Such parts of the work must, as far as we can judge from our knowledge of the parties engaged, and of the materials which they possess, form the most complete monographs ever published.

Upon the whole, we feel no hesitation in strongly recommending this work, as a desirable acquisition to those who are interested in that branch of natural history which it is intended to illustrate.

ART. III. A Synopsis of the Family of Naïades. By Isaac Lea, Member of the American Philosophical Society, &c.

THE rivers in North America, and especially those to the west of the Alleghany range of mountains, abound with an astonishing variety of species belonging to Lamarck's family