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in the same year, a third naturalist, without the knowledge of either Decandolle's Mémoire or the Hora Entomologica, and in a different part of Europe, publishes what he considers to be the natural arrangement of Fungi. Arguing à priori, this third naturalist fancies that the determinate number into which these acotyledonous plants are distributed ought to be four; but finds it necessary, in order that it may coincide with observed facts, to make it virtually five. Nay, at last, in spite of the prejudice of theory, he is unable to withstand the force of truth, throws himself into the arms of Nature, and declares that where he actually finds his natural group complete in all its parts, there the determinate number is five.

Now, on considering that his work was given to the world two years after the first part of the Hora Entomologica, it is clear that, had M. Fries fixed at once on the number five, there might have been room for supposing, that he had not altogether trusted to his own observation, but had borrowed the idea of a quinary distribution. As matters however at present stand, this supposition cannot for a moment be harboured; and I cannot help rejoicing that the strength of this beautiful theory should be so completely brought home to the conviction of every mind, as it must be, by observing the manner in which different persons have respectively stumbled upon it in totally distinct departments of the creation. We may all possibly be wrong in part, or even in much of our respective details; but however this may be, it is difficult not to believe that we are grasping at some great truth, which a short lapse of time will perhaps develop in all its beauty, and at length place in the possession of every observer of nature.

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It may be well to note, that M. Fries draws in the clearest manner a distinction between his Hysterophyta or Fungi, and the Protophyta, which is a natural group consisting of the Linnæan Alge and Lichenes. He proves that they form two distinct series of vegetables having analogous exterior forms at their corresponding points. Hence, according to what has ceded, the Protophyta and Fungi form in the vegetable kingdom two primary groups of equal degree. In Protophyta fructification is secondary, and the thallus essential; whereas in Fungi it is quite the reverse. According to our author the first-born of Flora may all be accounted as essentially roots, and representing the mode of nutrition; while every fungus is as truly and representatively connected with fructification and reproduction. Throwing aside other considerations, we may perceive the analogous groups of the animal kingdom to be likewise constructed on a similar plan. Each of the Acrita, for example, imbibing nourishment at every pore of their surface, internal or external, is essentially a stomach, while the situation of the singular ovaries of the Radiata cannot fail to remind us of the importance and position of the sporidia in Fungi. The umbellate Medusa,

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the Echinus, the Asterias, and the Priapulus have all their representatives in mycology, of which the genera Lycoperdon and Phallus are noted instances; so that the analogy of the Radiated animals to Fungi is complete; and we thus have in organized matter the following two series of groups connected by affinity and analogous at their corresponding points.

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Consequently some general idea of the primary distribution of all organized beings may be obtained from the following figure.

* This last department of the vegetable kingdom, Pseudo-cotyledonea, has been defined by M. Agardh in the sixth part of his Aphorismi Botanici, which is dated Dec. 1821. According to him it embraces the Musci, Hepatice and Filices of Linnæus ; and in p. 76 of the same work we find a comparison made between these plants and Amphibia, which is nevertheless much stronger when applied to them and the Mollusca. "Pseudo-cotyledoneæ Amphibiis non dissimiles, humum perreptant vel rimas quærunt, humiditateque gaudent ut illa, organis jam in superiore sectione deperditis iterum instructæ." In these last words he alludes to his own opinion, that Mosses display organs nearly related to the cotyledons of dicotyledonous plants, while the monocotyledonous plants conceal their cotyledon; and if botanists should adopt this opinion, we might assimilate it to the curious fact, that in the animal kingdom the imperfectly organized Mollusca display a heart, which is more analogous to that of the Vertebrata than the dorsal vessel of insects. With respect, indeed, to the analogies existing between the animal and vegetable kingdoms, they are too striking to have altogether escaped the notice of such an observer as Agardh, who truly observes, "Memorabilis est analogia evolutionis seriei vegetabilis cum animali." When we find him, however, comparing the least perfect vegetables to some of the most perfect animals, the Alga to Fishes, and the Lichenes to Insects, we must suspect that he is not sufficiently acquainted with the evolution of the animal series, and conclude that he has at least not sufficiently attended to the parallelism of analogy. Nevertheless, his comparison of Monocotyledonous, or, as he terms them, of Cryptocotyledonous Plants to Birds, appears to be a true relation of analogy, although an indirect one; and if he had paid that attention to Entomology which the science really merits, so acute a botanist, could not have failed to perceive, that the arguments he gives in support of this last analogy, only receive their full force when they are employed in the comparison of Monocotyledonous Plants with Insects. Thus, in the same page, he states aëriferous cells to be peculiar to Birds in the animal kingdom, evidently not aware that many more animals than are in the whole department of Vertebrata would have no means of getting their fluids aërated did not the air enter their bodies and penetrate through every part of them. But on this head Desfontaines long since set the scientific world at rest, when he established the relation of Dicotyledonous Plants to Vertebrata, and of Monocotyledonous Plants to Annulosa, not on external appearance merely, but on such primary principles of their respective structures, that we may almost term the former tribe of plants Vertebrated, and the latter Annulose. It would scarcely be fair however towards M. Agardh, did we conceal the fact of his being perfectly aware of the analogies which reign both between the Dicotyledonous Plants and the typical group of Vertebrata, and between the Fungi and Radiata. With respect to this last analogy, indeed the following words are perhaps more explicit than those previously published, p. 211 of the Hora Entomologica-" Fungi superiores animalia Radiata ob figuram radiantem, ob superficiem nudam, ob texturam laxam, ob colorem subsimilem non male revocant."

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To conclude: If an arrangement be natural, it will stand any test; and to support the truth of this proposition, I shall now arrange Annulose Animals in the same way that M. Fries has distributed his Fungi, when it will readily be seen as virtually nothing else than the arrangement I offered to the public in the Hora Entomologica. Thus it is only necessary that instead of subjecting Nature to arbitrary rules of our own invention, we should humbly receive her laws as she clearly proclaims them; when she will indeed appear, as M. Fries has found her to be, "ubique varia, semper tamen eadem."

Classification of ANNULOSA on the same Principles as those adopted by M. Fries in his natural Distribution of Fungi. ANNULOSE ANIMALS, which are not hermaphrodite or the ANNULOSA of Scaliger may all be divided into two groups founded on their larva or foetus state, viz.

1. Apterous Insects, having either no metamorphosis in the usual sense of the word, or only that kind of it the tendency of which is confined to an increase in the number of feet.

These are the APTERA of Linnæus, and comprehends three classes, viz. Crustacea, Arachnida, and Ametabola, which would be termed Radii by M. Fries.

2. True Insects, being all subject to that kind of metamorphosis which has a tendency to give wings to the perfect or imago state, but never more than six feet.

These are the PTILOTA of Aristotle, and should, according to M. Fries, be termed the Centrum of Annulose Animals. "Sed centrum abit semper in duas series," and consequently we find that the

New Series, VOL. VI,

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N. B. A mark of doubt is annexed to the word Trichoptea, because entomologists have not yet determined whether the Linnæan genus Phryganea forms part of an annectent order, or whether it forms a distinct osculant order.

ARTICLE III.

On the Composition and Equivalent Numbers of certain crystallized Muriates. By R. Phillips, FRS. L. and E. &c.

WHILE Correct views of the nature of chlorine and most of its compounds have been derived from the researches of Sir H. Davy, it appears to me that the attention of chemists has not been sufficiently directed to the consideration of the nature of some compounds which may be considered either as muriates or as chlorides containing water. In the first volume of the Annals, N. S. I gave a statement of the different views which may be entertained of those salts, which must be regarded either as chlorides or muriates. I now return to the subject, from having lately had occasion to employ the salt usually called muriate of barytes in such proportions as contained a certain quantity of the earth.

In order to ascertain the equivalent number of this salt, I consulted Dr. Thomson's table of the weights of atoms, given in the last volume of his System of Chemistry; in this we find the composition of chloride of barium, but not of muriate of barytes; and under the head of muriate of barytes (vol. ii. p. 264), the reader is referred to chloride of barium for a description of it. "The easiest method of preparing it," says Dr. Thomson, "would be to dissolve carbonate of barytes in muriatic acid, and crystallizing the solution." "The primitive form of this chloride," he continues, “is, according to Haüy, a four-sided prism, whose bases are squares. It crystallizes most commonly in tables." (System, vol. i. p. 357.) From this quotation it is, I think, evident, that Dr. Thomson considers the crystallized muriate (for so at present I shall continue to call it) as a mere chloride, and he does not mention that it contains any combined water: he certainly observes, "that when heated, it decrepitates and dries," but this seems merely to refer to accidental moisture.

On Dr. Wollaston's scale, dry muriate of barytes is mentioned, and this is of course the chloride of barium, for the number by which it is represented agrees as nearly with that assigned by Dr. Thomson to the chloride as 131 to 132.5 In the memoir in which the scale is described by its author, crystallized muriate of barytes is represented as consisting of muriate of barytes 131+2 water = 22.6; making the number for crystallized muriate of barytes 153-6; it is singular that Dr. Wollaston has not placed this upon the scale, for as the salt usually occurs in the crystallized state, it is that in which it is most used, and in which the knowledge of its equivalent is most desirable. Mr. Brande (Manual, vol. ii. p. 82), appears to agree with Dr. Thom

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