Leaving out the four strongly aberrant groups placed at the end of the series, the mass of the typical Acanthopterygians, it will be observed, are divided into 16 divisions, containing altogether 43 families, the greater number of which are newly defined. These “divisions" are mostly named from the title of the most typical or best known genus, to which the termination-formis is added, and consist of one or more "families," as the case may be. The arrangement thus given is completely new, and in fact has only been perfected since the termination of the working out of the whole group, as it will be noticed that the species as given in the text of the three volumes, do not follow this consecutive order.

Dr. Günther's fourth volume contains the two orders Pharyngognathi acanthopterygii and Anacanthini, of Müller. In dealing

with the former of these orders Dr. Günther has deviated from Müller's arrangement-changing the name into Acanthopterygii pharyngognathi-as he considers the structure of the fins a more important character than that of the pharyngeal bones. He also omits altogether the soft-finned Pharyngognaths of Müller (Scomberesocidae), not considering the coalesced pharyngeal bones as a character of sufficient importance to unite acanthopterous and malacopterous fishes in the same order. The Anacanthani on the other hand (which coincide essentially with the Malacoptorygii

jugulares of the old authors) appear to Dr. Günther to be a very natural order, although the want of symmetry in the Pleuronectidæ would at first sight induce one to distinguish them rather strongly from the symmetrical Gadide and their allies. But, as Dr. Günther reminds us, the absence of symmetry in the latter is the only constant character upon which such a distinction can be made, and in the more highly organized Pleuronectidæ (such as Psettodes) this character is but little developed. On the other hand the Gadidae and Pleuronectidæ agree in other important characters, such as the great development of the dorsal and anal fins, the position of the ventrals, and the increased number of the caudal vertebræ.

Dr. Günther gives 1090 species of Acanthopterygii Pharyngognathi and Anacanthini, of which he considers 890 to be well characterized. There are a great number of new species described in these two orders, particularly in the families Chromida and Pleuronectidæ. In the former groups the freshwater lakes of Guatemala, lately explored for the first time by Messrs. Salvin and Godman, have yielded an abundant harvest, and we believe a special communication of Dr. Günther on this subject, with figures of many of the new species, will shortly appear in the Zoological Society's "Transactions."

Dr. Günther's fifth volume commences the series of those families of Fishes, which Müller called Physostomi, from the air bladder being connected with the pharynx by an air-duct. The extensive family of Siluroids is taken first, of which nearly 700 species are known, and the details of which take up the greater portion of the volume. These are followed by the Characinoids and several other smaller families. Amongst these perhaps the most noticeable in the way of novelty is a new genus of Australian freshwater fish called Prototroctes-the representative of the Salmonoids of the Northern Hemisphere in the Antipodes. The genus is of greater interest as being naturally associated in one family with the genus Haplochiton of Jenyns, discovered by Mr. Darwin, during the voyage of the Beagle, in the freshwaters of the temperate parts of South America, and thus giving us a new link between the Fauna of Australia and that of South America.

Dr. Günther's fifth volume is also of great importance in making such extensive additions to our knowledge of the fishes of the Nile basin-the Silurida and Characini, being as is well known very fully

developed in the freshwaters of the Ethiopian as well as in those of the Neotropical region.

The whole of Dr. Günther's fifth volume contains 1005 species, against 492 in the corresponding portions of Cuvier and Valenciennes' work. Of these 849 are considered to be undoubtedly

valid specimens.

In conclusion we heartily wish Dr. Günther health and strength sufficient to carry his great and important labours to completion-of his industry, and of his ability (in other ways) to finish what he has begun we have no doubt. It is no small task, as our readers must acknowledge, that has already been accomplished-that of naming, cataloguing, and describing some five or six thousand species; and those who know the energetic author of the "Catalogue of Fishes" are well aware, that these volumes are by no means the only products of Dr. Günther's laborious industry during the last six years. The work, however, is now more than half accomplished, and we trust that another five years will see the "Catalogue of Fishes" complete. Its effect upon the study of Ichthyology will in all probability be very remarkable. We cannot suppose that more than a fourth part of the fishes now in existence are yet known to science, nay, perhaps, not more than a tenth part, for of many parts of the world the Pisci-fauna is almost unknown. The fact is that the study of these creatures has been hitherto greatly obstructed by the want of a convenient book of reference, wherein what is at present known is summarized and brought together. The publication of Dr. Günther's Catalogue will therefore, no doubt, give a great and immediate impetus to the study of fishes-indeed we may say in relation to the published portions that it has already done so. Its immediate effect will be in all probability an increase of at least ten per cent. in the number of described species of this class of Vertebrates. It has already operated well for our National Collection in inciting the accession of a very large number of valuable additions to this department, as will be seen by reference to the long lists of donations and purchases given at the commencement of each volume of the catalogue. It has also been of the greatest service to the collection in another way--we mean in enabling selections to be made out of series offered for sale. Until a collection has been properly named and catalogued there is of course perpetual risk of acquiring duplicates when new purchases are made, or of rejecting new specimens. As the catalogue advances this risk diminishes, and the means for

acquiring serviceable additions proportionately increase. At the completion of Dr. Günther's labours, therefore, he may fairly look forward to having under his care the largest as well as the most perfectly catalogued series of Fishes in existence.

IV. SIEBOLD'S EUROPEAN FRESHWATER-FISHES.

DIE SÜSSWASSERFISCHE VON MITTELEUROPA. Bearbeitet von C. Th. E. v. Siebold. Leipzig, 1863. 8vo.

WE believe that a feeling of some surprise, mixed with no little curiosity, was excited among zoologists, when it became known that one of the editors of the "Journal für Wissenschaftliche Zoologie," had descended to the level of ordinary Zoology-we mean the Zoology of the old school, which considers an animal worth examining, even when this can be done without the aid of the microscope and the dissecting needle. Would one of the founders of the modern German school of "scientific zoology" treat his subject in a new style? Would he discover new ways of distinguishing species, and put forward hitherto unknown views leading to a more perfect systematic arrangement? Would he teach us, as we have been taught in the case of the North American Tortoises, that to study the adult animal is useless, and that to understand specific and generic affinities, we must examine embryonic and subembryonic conditions? How far conjectures of this kind were verified by the result we shall shortly see.

When Bloch, the celebrated German Ichthyologist of the last century, humbly requested Frederic the Great to order certain officials to aid him in collecting the fishes of the Mark of Brandenburg, he received the reply: "I am glad to hear that you occupy yourself with fishes, but what you ask of me is nonsense; for I know all the fishes in the Mark myself. There are carp, sander, perch, and eels. Are you going to count their bones ?" We need hardly say that Dr. v. Siebold found his Government more enlightened than this. In fact, the present work owes its origin to the order he received from it to prepare a report on the fishes of Bavaria-and as by degrees he extended his researches far beyond the limits first assigned to it, he not only enjoyed material assistance from his own rulers, but also obtained aid from the governments of neighbouring countries. Having devoted nine years to a

study which he found infinitely more difficult and time-absorbing than he had anticipated, he presents us with the results of his labours in an octavo volume of 430 pages, illustrated by 64 woodcuts, and 2 coloured plates.

The somewhat lengthy introduction to Dr. von Siebold's volume is evidently written for that part of the public which does not care much about the information which they might gather from the work itself. In this the author describes the ordinary ways and means of collecting materials and information, which are familiar to every one who has studied any portion of a particular fauna. The introduction is followed by a complete and excellent review of the literature bearing upon the fishes of Germany, whereby the author evades the usual practice of quoting in the synonymy of each species every author who has ever noticed it. This is a method far superior to the one in which valueless works and names of would-be naturalists are promiscuously quoted along with original descriptions and scientific authors. From the author's own assertions in his introductory remarks and especially from the synonymy itself, it is evident that he places himself on the side of those Zoologists who would counteract the mischief done by Agassiz, Valenciennes, Bonaparte, and Heckel, in introducing into ichthyology the custom of splitting up species and genera on the slightest and most insufficient grounds. "The catalogue of our freshwater-fishes," says Dr. v. Siebold, " abounds with untenable species. This nuisance has been partly caused by systematists who have carried the multiplication of the genera so far, and who have defined the characters of these genera so indistinctly, that in consequence of their insufficient examinations they were obliged not only to separate fishes which must be referred to the same species by every unbiassed observer, but even to place them in two distinct genera, in obedience to the principles of their unnatural system." Of the authors mentioned none fares worse than Heckel, and although Dr. v. Siebold pays him all those compliments which celebrated savants usually pay to one another, the synonymy of almost every species shows, that he has no great opinion of the discriminating powers of the man who endeavoured to make Vienna the head-quarters of our knowledge of European freshwater-fishes. For although out of Austria there never was much doubt as to the scientific value of Heckel's genera and species, it required a publication like the present to entirely supersede the "Süsswasserfische der Oesterreichischen Monarchie," and to thoroughly