molluscous animals, form no distinct perception of objects, though they are directed by the visual organs they possess to seek or shun the light, as circumstances may require. We feel inclined, from a variety of considerations, to think that the ocular points of the leech are really eyes, such as exist in some of the invertebrate animals.

Certain differences are described as existing in the teeth of the Hirudo Sanguisuga, whose ordinary food is stated to be, the common earth worm, which it breaks into convenient pieces, and swallows. The Hirudo Vulgaris is oviparous; the process of reproduction is very minutely described by M. Carena. The young quitted the eggs, or general envelope, on the 21st day; the number of germs in any egg was never more than twelve, nor less than nine; but then it always happened that one or two of them proved abortions.

nata.

There are circumstances in the history of the Hirudo Complanata which may possibly determine the naturalist at some future period to remove this animal entirely from the genus Hirudo. It rarely moves; never swims, and its ordinary dimensions present the maximum of contraction of which its body is capable. The Hirudo Cephalota, which is viviparous, is, in the same circumstances as to arrangement with the ComplaThe Trioculata, described as a very rare leech, does not swim. On the subject of the locomotion of the leech, M. Carena thinks that the terminating disks of this animal adhere to the substance on which it creeps, by the simple adhesion of surfaces, and not by any real suction. He remarks that the animal still adheres to the surface on which it is placed, even though a portion of the disk has been forcibly detached; an experiment which, if correct, entirely overthrows the usually received notion of any vacuum having been formed. We confess we are still inclined to adhere to the old opinion.

Of the experiments on mutilated leeches, alluded to by Professor Carena, one only has been detailed minutely. The leech was of the species he has called Provincialis, and was cut transversely into three portions, in the last week of February 1820. The middle portion alone was preserved in water renewed daily. This fragment was composed of 40 segments, and excluded the sexual openings. The wounds cicatrized in a few days, leaving in the centre an opening, which was the section of the alimentary canal.

This fragment proved very tenacious of life. It moved frequently about the porcelain dish in which it was placed, advancing always the extremity which corresponded to the head. It frequently changed its epidermis, and excrements issued from time to time through the posterior extremity. These appearances continued to present themselves until the middle of July, when the author, having occasion to quit home, with the view of completing this very Monograph, of which we now render an account, entrusted the fragment to one of his colleagues, Professor Rossi, with whom it was still alive on the 10th December 1820, i. e. about ten months after the date of the experiment.

ART. XXIX-NOTICES OF RECENTLY PUBLISHED
BOTANICAL WORKS.

GREAT BRITAIN.

It was our intention here to notice particularly the contents, and to offer some remarks upon those which appeared the most important, of the following publications. The number, however, of these articles, and the degree of space which is already occupied by other botanical subjects, effectually prevent our doing this so fully as we had anticipated; and we must reserve to ourselves the agreeable task of investigating these works in a future number, and confine ourselves, at present, to giving little more than a list of their titles.

Systematic Botany.

Under this head we have peculiar satisfaction in announcing the long expected account of the Botany of Melville Island, by Robert Brown, Esq. which forms one portion of the Appendix to Captain Parry's First Voyage, under the title of a List of Plants collected in Melville Island, by the Officers of the Expedition, with Characters and Descriptions of the new Species. We find, in this production, the same acute research, combined with that wonderful correctness of observation, that characterize all this gentleman's writings: and although from several causes, of which an ill state of health was the principal, Mr. Brown did not extend this Memoir, especially, as he had intended, to what concerns the comparison between the state and relative proportions of the primary divisions and natural orders contained in this list, and a parallel between the vegetation of regions in nearly similar climates and latitudes; yet the botanical world, highly as its expectations have been raised with respect to this publication, will feel no disappointment in investigating its contents. The number of species amounts to 116.

Smith's English Flora.

THE British botanist will have great pleasure in hailing the appearance of the first two volumes of the English Flora, by Sir James E. Smith, President of the Linnean Society, &c. &c.; a work which, as might be expected from the hand of such a master, will unquestionably hold a first rank among publications of the kind. Notwithstanding all that had been done among the vegetables of the British Isles, by the same learned author, in his two works, the English Botany, and Flora Britannica, so many, as he himself states, have been subsequently discovered, and so many alterations and improvements have taken place in the science, that he found it necessary to commence the present undertaking as an entirely new work; a character to which the book itself amply justifies its pretensions.

The whole is written, as may be inferred from its title, in the English language, and is arranged according to the system of Linnæus; the

two volumes including the first twelve classes, from Monandria to the end of Icosandria. The remaining volumes are anxiously expected.

Dr. Greville's Flora Edinensis.

ANOTHER work, that peculiarly claims the attention of those who are interested in the botany of Scotland, is the Flora Edinensis, or a " Description of Plants growing near Edinburgh, arranged according to the Linnæan System, by R. K. Greville, LL.D. F.R.S. Edinburgh," &c. With a degree of perseverance that does him high credit, this author has most successfully explored the botanical productions of the environs of that romantic city, as is evident from the great number of species that he has accumulated within a radius of ten miles from the town, whether growing in the fields, upon the hills, among the woods, or on the sea shore. The particular stations are very fully stated, together with generic and specific characters, and remarks; and the whole is arranged with great correctness, according to the artificial classes and orders, although each genus is headed by the name of the natural order to which it is referred, according to the most approved method.

But what will render this book valuable, not only to the botanists of Scotland, but to all who desire to be acquainted with the vegetable productions of the British kingdom, is the great attention which Dr. Greville has devoted to the class Cryptogamia, and particularly to the Fungi. Considered in this light, the Flora Edinensis is the first work, in which the Fungi of any portion of this country have been arranged with much precision, as to what concerns their families and genera, Dr. Greville has taken advantage of what has been effected by all the recent continental writers on the subject, and has introduced many new and valuable improvements. References, too, are of course given to the figures in the author's Scottish Cryptogamic Flora, where a great many new genera, as well as new species, are admirably represented, accompanied by such dissections as render them of the highest importance to the student of this difficult but interesting family of plants.

Mr. Roscoe's Monandrian Plants, of the order Scitamineæ.

It is well known that Mr. Roscoe, who has made so many and so great improvements in what concerns our knowledge of the plants of the natural order Scitamineæ, has long been meditating a splendid work, with figures of this highly curious and beautiful family. The first number of this publication has recently appeared, bearing the title Monandrian Plants of the order Scitamineœ; chiefly drawn and coloured from living specimens in the Botanic Garden at Liverpool, and other conservatories; arranged according to the System of Linnæus, with descriptions and observations, by William Roscoe, Esq. Associate of the First Class of the Royal Society of Literature," &c. &c.

If we consider the peculiar utility of this tribe of plants, many of them producing valuable spices, medicines, and dyes, as the Zedoary, the Cassumanar, the Cardamom, Ginger, Arrowroot, &c. as well as the delicate beauty of their blossoms and their foliage, we must allow that

the venerable historian of the Medici could not have selected a subject more worthy to be illustrated by his taste and judgment throughout the whole range of botanical beauty and interest. The garden, too, of Liverpool, which owes so much to this gentleman, has, under his patronage and advice, seconded by the judicious direction of its curators, Messrs. J. & H. Shepherd, become possessed of such treasures in Scitamineous plants, received from Africa and from both the Indies, as no other collection in the world can equal. Possessed of these advantages, Mr. Roscoe commences the present undertaking: and most sincerely do we wish him health to complete his labours, the result of which will redound as much to his own credit, as it will to the advantage of science. The whole work will be comprised in eight numbers.

No. 1. contains one Canna, C. flaccida of Salisbury and Redouté; one species of Phrynium, P. parviflorum of Roxburgh's Fl. Indica; two Hedychia, H. glaucum, Roscoe, (allied to H. gracile of Fl. Indica,) and H. longifolium, (allied to H. carneum of Loddiges ;) two Alpiniæ, A. calcarata of Roxburgh, and A. mutica of Roxb.; Zinziber officinale, the Ginger of the shops, which but very rarely produces its flowers; and lastly, Kampferia marginata of Dr. Carey's MS.

The descriptions and remarks are entirely in English. The plates are executed in lithography, and coloured under the superintendence of Mr. Graves; and the whole is upon an imperial folio size, the plates and descriptions being contained in a portfolio.

Some account of the periodical Botanical works, as Sims' Botanical Magazine, the Botanical Register, Loddiges' Botanical Cabinet, and Hooker's Exotic Flora, will be given in our next Number.

CONTINENTAL BOTANICAL WORKS.

New Deutschland's Flora.

Ar the same period that the learned President of the Linnæan Society is engaged in editing the Flora of our native country, in our native tongue, Professor Mertens and Dr. Koch of Bremen are similarly employed in compiling a Flora of Germany, in the language of that empire, entitled, "Deutschland's Flora," which, from the well-known celebrity of its authors, will, it may safely be argued, far exceed in importance every other publication on the subject that has yet appeared in that country.

Of this likewise two volumes have appeared; but the first is occupied with an excellent dictionary of botanical terms. The second begins the descriptive part; and so fully and minutely have the authors described the genera and species, that although the volume contains nearly 900 pages, it comprises no more than to the end of the 4th class.

We cannot help noticing the typography of this work, as far excelling that which we have ever seen employed in publications of this kind, proceeding from the German press; and the paper likewise, (we speak, however, from a presentation copy,) cannot be surpassed, either for quality or colour.

De Cundolle's Prodromus Systematis Naturalis Regni Vegetabilis. ONE of the greatest desiderata among botanists has hitherto been an Universal Flora, arranged according to the Natural Orders; and if we were asked to point out the individual who was best fitted for such an undertaking, both by his vast knowledge and his great activity, we should unquestionably have fixed upon the eminent name which stands at the head of this article. Professor De Candolle commenced this important task, as is well known, with the Regni Vegetabilis Systema Naturale, sive Ordines, Genera et Species Plantarum, secundum methodi naturalis normas digestarum et descriptarum, which extended to two volumes, each comprising between 600 and 700 pages, yet containing only the first eleven orders of M. De Candolle's arrangement, the last of them being the Cruciferæ, or about 2000 species.

Upon such a plan, including, as the Flora of the world now does, upwards of 50,000 known species, the work would have extended to a very great number of volumes, and have occupied the greater portion of the life of the esteemed author. Under this impression, Professor De Candolle was induced to alter his plan; and, before proceeding with the large work, to edite with all the dispatch possible, consistently with the nature of such an undertaking, a Prodromus Systematis Naturalis Regni Vegetabilis, sive Enumeratio contracta Ordinum, Generum Specie rumque Plantarum hic usque cognitarum juxta methodi naturalis normas digesta; in which it is expected that all the known plants may be included in four very closely printed 8vo. volumes. Of this publication the first volume has appeared, containing the first 54 orders of De Candolle's sub-class Thalamiflora, and above 6000 species. The department, which has cost the author the greatest labour, and on which he justly sets the highest value, is the natural arrangement in the genera, a subject which has been hitherto almost wholly neglected. This is effected, in most instances, by the division of the genera into sub-genera, or natural sections, to which are affixed proper names and characters taken from the fructification, (as in the case of actual genera,) but which do not alter the known appellations of the species. By means of this method, originally adopted in Zoology, the necessity of constituting new genera, and altering old established names, is avoided, and all the utility of order in classification is preserved. The whole is very closely printed upon 750 pages, and is published at Paris.

We may here mention, that Dr. Hooker, Professor of Botany in the University of Glasgow, is at this time engaged in preparing an Universal Flora, in the English language, in which he will follow entirely the arrangement, and, in many instances, the generic and specific characters, which have been adopted by De Candolle in his Prodromus. Every new species to which Dr. Hooker can obtain access, will besides be added, and the work will be accompanied with plates, drawn by himself, illustrative of the natural orders. The first part will appear at the commencement of the ensuing year.