5. Die Wanzenartigen Insekten, getreu nach der Natur abgebildet und beschrieben, von Dr. C. W. Hahn. Iter Bd. 6 Heft. er Bd. 4 Heft, Nurnberg, 1833-34.

6. Histoire Naturelle des Insectes.-Diptères, par M. Macquart. Tom. Ir, accompagné de Planches. Paris, 1834.

7. Abbildungen zur Berichtigung und Ergänzung der Schmetterlingskunde, besonders der Microlepidopterologie, als Supplement zu Treitschke's und Hübner's Europäischen Schmetterlingen, mit erläuterndem Text. Herausgegeben von J. E. Fischer. 2tes Heft. Leipzig.

8. Delectus Animalium Articulatorum, quæ in itinere per Brasilium, annis 1817-20, jussu et auspiciis Maximiliani Josephi I. Bav, Reg. August. peracto collegerunt Dr. J. B. de Spix et Dr. C. F. Ph. de Martius. Digessit, descripsit, pingenda curavit, Dr. Max. Perty. Fasciculus III. cum 16 tabulis. Monachii,

1830.

THE last fifteen or twenty years have done much for the science of Entomology, in its nomenclature, in the addition of species of insects, and in their systematic arrangement, and, more than this combined, in rendering it a favourite and popular science, by the dispersion of prejudice and the diffusion of a taste for the investigation of objects so replete with all that can prove attractive. We much wonder that it was so long neglected, and not equally culti vated with its sister science Botany, over which it possesses innumerable advantages, although not in so direct an application to the necessities and comforts of man, to which it however contributes very largely; but in that development of intellect resulting from its due cultivation, and the very effective arguments it adduces in support of the doctrines of natural theology. It had long to contend against the repugnance produced by either the form or habits of some of its individuals; but surely that mind must be very feeble which allows itself to be influenced by such considerations. Is any thing, we would ask, that proceeds from the hands of the great Creator too insignificant for man to investigate? A moment's reflection will apprise us that the most minute insect must necessarily be as fully perfected in its structure, in its wonderful apparatus of nerves, muscles, respiratory organs, and organs of the senses, and all their functions, and its system of circulation, (proved by recent discoveries,) as the largest, and, according to its rank in nature, the most gigantic animal, over which it possesses an infinite superiority of muscular strength; and, when we find that there are insects scarcely discoverable without a lens, must we not exclaim with wonder and admiration at the stupendous power evinced in their construction? and should

not this stimulate us to learn as much as we can concerning these miracles, that we may be better able to appreciate the marvellous power displayed in their creation, although we can scarcely hope to arrive at the perfect comprehension of their least attributes, the complexity of their organization, when even most simple, the multiplicity of their instincts, the quality of those instincts, and their very powerful agency in supporting the universal equilibrium of nature? Who then is bold enough to say, even to what his arrogance and assumption have dared to style a contemptible insect, "Thou art beneath my notice," when he feels that the pigmy might reply, "Thou, with all thy boasted superiority, dost not comprehend me?" Humility is the crown of humanity, and let us follow the words of Solomon and learn wisdom from the ant.

The inducements to the study of natural history in general are too multifarious to be dwelt on here: among the strongest in favour of entomology is its exhaustlessness and the vigour thence derived to the faculties, and that mental equanimity and suavity of temper, the necessary concomitants of health, produced by exercise in the air; for, when we speak of the study of Entomology, we would be understood as pursuing it chiefly in the fields, for there alone is that most desirable portion of our knowledge to be culled which refers to the instincts and habits of the

creatures.

The objects of the science appear to comprise, 1st. A systematic knowledge of the species and their subdivision into genera and all the superior combinations it may be thence desirable to form; and, 2dly, the history of each species, which contains the details of its metamorphoses, anatomy, habits, economy, instinct, and mode of propagation. One result of this knowledge will be the power of applying them to our uses when thus available, or of curbing the injuries inflicted by them, by teaching us to restrain their diffusion; another and more important result is the instruction it instils of the subserviency of each individual to the good of all, and of their mutual and relative dependency, thus presenting a splendid view of the universal harmony of nature, and thereby inculcating the bounteous benevolence which devised the scheme and which has so consolidated the laws that regulate it, that we can see in it nothing less than the eternal presidency of an omniscient and omnipotent Providence. The study, therefore, of this science, and of nature generally, has as evidently moral and religious tendencies, as it is intellectual and economical.

The knowledge of species being thus evidently the basis of the science, it is important that their differences should be philosophically characterized and the character also clearly determined,

which group them, apparently naturally, into genera; and these likewise should be as obvious and perceptible as it is possible to make them. The generic character will therefore be a table of resemblances for the group beneath it, and of differences for all collateral groups, and consequently cannot truly admit of sections and subdivisions, which are merely aids for the more ready determination of an individual. The same axiom applies to all the several branches into which the class may ramify; the aggregate of character necessarily diminishing the closer we approach the stem, so that it is perfectly immaterial how numerous these consecutive divisions may be, or what may be their names. But species being the final subdivision of organic conformation, for varieties are mere contingencies which obey no law, it follows that the foundation of the science consists of species, the knowledge of which includes the whole learning of the science. It was reasoning thus, that Linneus in Botany, and Fabricius after him, applying it to Entomology, severally laid down this maxim: "Quo plures entomologus noverit insectorum species, eo ceteris paribus etiam præstantior erit, quum omnis vera cognitio humana cognitione specierum nitatur," and the importance of an extensive acquaintance with species is shown by each containing within itself, in regular synthetical progression, every definition which analysis has previously framed for the systematic distribution of the series.

This proves its value were the systema thus logically constructed, and each collateral division, bearing the same name, of equivalent value; but, as we find that Nature will burst through every bodice we endeavour to invest her with, for none hitherto framed has been found to fit her, it becomes still more apparent that a profound knowledge of species is indispensable, as they even vary in structure, which is a character that should always be generic, whether it be sexual or common; but which rule entomologists have been hitherto, perhaps, too modest to adopt, when such an anomalous genus contains but few species; but which, as these increase, and every day contributes to this effect, it will be found important to have recourse to. Robineau Desvoidy, in his "Essai sur les Myodaires," is the only instance present to our minds, who has proceeded upon this principle. The specific character will therefore necessarily be important to attend to; it is a detail of the trivial differences inter se, and thus may be adapted to suit present purposes, and can be reconstructed and altered, if rendered desirable by the accession of new species.

But the specific description, if the species is to be permanent and not liable to the casualties of mistake or insufficiency, should

absolutely contain every thing in the fullest possible description of the external appearance of the insect which is not common to its congeners, and which, consequently, has not already entered into any of the definitions of the superior subdivisions, for they can never be founded upon characters liable to vary, which will necessarily remain merely specific. The latitude which these may be allowed to take without affecting the identity of the species, must be left to the experience of the monographer; as there are many instances wherein extreme varieties have been considered species, until further information and a series of individuals have proved them to be identical. This shows the importance to be attached also to a familiar acquaintance with varieties. Such a full and detailed specific description, is not always required for immediate use, for which frequently much less would suffice, but to meet the possibility of future contingencies from the discovery of new insects; and the utility of an ample description is evinced by the doubt attached to the identity of many insects described by Linneus, Fabricius, and still later writers, from the error of not taking this comprehensive view of the probability of future discoveries. It is also more philosophical and truly scientific that every thing that will bear record should be inscribed and entered in the registers of the science.

It is therefore to the monographer that we must look for really profound and satisfactory information; but we fear it will be very long before all the requisitions for a good monograph, as stated by Godet, will be answered. Indeed the difficulties which surround it are, we may almost say, insuperable; and it will not be until they are overcome that we can boast of possessing a complete natural history of insects. But it is progressing; and the fundamental knowledge of species is a great step towards it. If we complain of the paucity of information upon the natural history of insects, it refers comparatively to the hosts of insects, of the manners of which we as yet know nothing; and it will be possibly very long before we arrive at any clear knowledge upon them beyond their mere arrangement. But the works we do possess upon the subject are admirable in execution. Systematic collocation gives us nothing decided upon the analogies of instinct; we cannot draw inferences from such premises, which is clearly attested by Huber's "Observations sur les Fourmis"-the species of the same genus differing very considerably in economy, and consequently in the instincts which regulate it. We will admit that structure is sometimes a tolerable guide, leading through function to habits, economy, and instinct, whence we may deduce general analogies; but it cannot be depended upon in reasoning upon particulars. Unfortunately, in this science, the minuteness

of the individuals, and their delicacy of organization, place great difficulties in the way of physiological investigation, the results of which, consequently, we fear, are but rude approximations in lieu of positive facts. The entomologist must be encouraged to the observation of facts, for all natural science is wholly dependent upon them. How infinitely more attractive and instructive are the labours and writings of Reaumur, Bonnet, the Hubers, Sprengel, and De Geer, as connecting the former with the following, viz. Swammerdam, Lyonnet, Herold, &c. &c., than those of the most ingenious systematist, howsoever refined his theory!--and these are the examples to emulate. We admit that they could not dispense with system; or where they unadvisedly endeavoured to do so, the world has lost the advantage of their observations. But, we would ask, where does Botany stand in comparison with Entomology? In the little we do possess upon this subject, where does it present us with such a pleasing and attractive generalisation as we possess in the first two volumes of the charming " Introduction to Entomology" by Kirby and Spence? We would advise all railers against Entomology to read those volumes before they again utter an opinion upon the subject; and, should that perusal fail to make converts of them, it will at least have the merit of divesting them of their prejudices, and we think they will admit that the time thus occupied has not been lost.

It seems hopeless to endeavour to arrive at any satisfactory conclusion relative to the probable number of the species of insects spread over the earth. Various calculations have been made, the discrepancies of which are perfectly ludicrous, if we view them without reference to the circumstances and data whence they were deduced. It appears plausible to argue from the materials in hand, namely, from any assiduously elaborated Fauna upon the relative numbers of the different orders;-for some, the Coleoptera and Lepidoptera have been very generally the favourites, and consequently more carefully and universally collected than either of the other orders; but still the result will be far from conclusive, for such a Fauna will necessarily be of a country seated within the temperate zones; and to conclude thence upon the relative numbers of the orders within the tropical regions, and of countries so differently circumstanced both in climate and geological structure, is merely to hazard conjectures without the least hope of even an approximation to the truth. The data whence they must proceed are exceedingly incorrect; for the number of the two orders which should form the basis of the calculation have not, in those regions, been yet so nearly ascertained as to enable us to form a clear idea, the minute species having been hitherto very much neglected. It has been generally supposed