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“As to the organs of nutrition, I select the most important of all, to wit, the vessels, and I consider them under that poiọt of view which is the most essential of alls-their presence or their absence. It is evident, in fact, that the anatomical circumstances which influence nutrition most powerfully, are the existence or non-existence of vesselsof those organs which seem at first-yiew so essential, that it is difficult to form an idea of the life of a being that is deprived of them. On this principle then, we will divide vegetables into two classes--vascular and cellular. This division appears to be connected with every thing most remarkable that the nutritive organs present. Thus, with the existence of vessels are found constantly united, 1st, the existence of stomata or cortical pores ; 2ndly, the evident distinction between the roots and the stem, consequently, the existence of a collum. The absence of vessels, on the other hand, announces, 1st, the absence of cortical pores; and 2ndly, the impossibility of distinguishing with precision the root from the stem. But to assure es whether this division is really natural, it is necessary to recur fo an examination of the organs of reproduction. Here let us ask, what is the first of these organs? Undoubtedly, the embryo, and the most important point in which it can be considered, is its absence or presence. Here then, with M. Richard, we might, in the first place, distinguish all plants into those with, and those without an embryo. But as we have no proof that any organized beings really exist without an embryo, and as it is impossible to establish the basis of a classification upon a question of fact which cannot be solved by our senses, let us change the question into the following :-admitting that there exists in all vegetables a germ or reproductive corpuscle, what part of that corpuscle is the most essential. It can be neither the radicle nor the plumula, which, by the hypothesis itself, is common to all plants; it must be then the cotyledons, that is, the special organ with which the reproductive corpuscle is furnished for its developement. We will then state that in the function of reproduction, that which is most essential, is to know whether the embryos have or have not cotyledons, and will divide vegetables into two classes, cotyledonous and acotyledonous. This idea is strengthened when we perceive that all the plants that are classed
among the acotyledonous, are the same that many authors sup pose to be destitute of an embryo. And it is remarkable, that by the two methods, we arrive at the same results ; thus the vascular vegetables are the saine" as those with cotyledons, and the cellular vegetables the same as those without cotyledons; and this division is natural.
"Let us now take the vascular or cotyledonous vegetables, and apply to them the same train of reasoning. “As to the organs of nutrition, we will take the first of these
organs, to wit, the vessels, and consider them no longer in the first point of view, as that has been already employed for the primitive division, but in a second, that is, their position, and establish their classification upon the position of the vessels. In this view it may be perceived, that there are vascular vegetables, where the vessels are all sensibly concentric around a cellular pith or cell, and arranged in such a manner that the oldest are in the centre, and the youngest at the circumference, whence it follows that the plant hardens from within to without. These we have distinguished by the name of Exogene, (wyświlw.) We may perceive, on the other hand, that there are other vegetables in which the vessels are scattered through all the stem, not ranged in zones around a central point, and disposed in such a manner that the oldest, that is to say, the hardest are at the surface, and the principal growth of the stem takes place within. From this peculiarity, is derived the name of Endogenæ, wbich we have imposed on this class. Besides the fundamental characters that we have just indicated, let us add that the Exogene have a canal and medullary rays of which the Endogenæ are destitute; that the first have a form necessarily more or less conic, whilst that of the second is really cylindric: that the age of the first is known by the number of concentric layers, whilst that of the second is measured by the number of rings more or less visible on the stem, when examined in a vertical direction. Let us add, the nerves of the leaves are generally branching in the exogenous, simple in the endogenous plants, that the leaves themselves are rarely sheathing in the first class, very frequently in the second.
“ Let us now consider the same vascular plants, as regards the organs of their reproduction. Let us select the most essential of these organs, to wit, the cotyledons, and consider them, not according to their number, as we have done before, but according to their position, which, as we have stated, is the most important of its characters, except that of its existence. Now.we will perceive that in this respect, vegetables are divided into two great classes, namely, those in which the cotyledons are opposite of verticillate; these, to conform to common usage, we will call dicotyledonous, and those in which the cotyledons are alternate, which we will call on the same principle, monocotyledonous plants. As these · cotyledons are in reality oniy the first leaves present in the seed, just as the radicle is but the root, and the plumula the stalk, it follows, from this disposition of the cotyledons, 1st. That the Dycotyledoneæ must have their primordial leaves opposite of verticillate, which may, however, become alternate by the act of vegetation ; that the Monocotyledoneæ, on the contrary, have the primordial leaves alternate, but which, in turn, may become verticillate or (more çarely) opposite. 2ndly. That the number of cotyledons is not fixed; in the dicotyledonous plants, it may vary from two, which is the most common number, to three, four, five and upwards; in the monocotyledonous it may vary from one, the usual number, to two as in the Cycas, which is, nevertheless, not a dycotyledonous plant, to three, as in certain grasses, &c. The number depends solely on the number of leaves already developed and visible in the seed.
“Now, if we compare the division of the vascular plants, with reference to their organs of nutrition or reproduction, we will find that the exogenous plants are exactly the same as the dicotyledonous, and the endogenous exactly the same as the monocotyledonous. This division then is also natural.-Theorie Elémentaire, doc. Paris, 1819. pp. 237, 242.
Even from this able exposition it is apparent, that however great has been the improvement which this system has made in the arrangement of plants, its own fundamental principles are
liable to some objections, and weakened by the uncertainty which hangs about them. The number of cotyledons apparently the very basis of the system is not invariable, * while the habit as arising from foliation is still more mutable. A wide field remains open to encourage and reward the labour of botanists; and this science has perhaps yet to receive its most important modifications.
M. De Candolle is one of those who have undertaken to remodel the system of Jussieu, so far at least as the arrangement of the orders is concerned. His reasons for this alteration, he has stated in his “Theorie Elémentaire,” which he considered as the preface to his “Systema Naturale," and if not so important as the doctrines he has just been examining, they, nevertheless, are worthy of our attention. After noticing that the vegetable kingdom resembles a geographical chart, much more than a continued chain of being, because as he afterwards observes “ each genus, each family does not only resemble the groups which immediately precede and follow, but has multiplied relations with many others. The linear order cannot shew us these relations, and yet it is the knowledge of them which constitutes, really, the difference between one classifier and another :" he continues
“All that I have been considering proves evidently, in my opinion, that there does not exist in nature any continued series ; that beings are grouped together at distances very unequal, and, that it is impossible to express their true relations in a linear order. But, nevertheless, for the accustomed form of our treatises, even for instruction and the arrangement of collections, it is necessary to adopt a series, understanding at the same time, that it is only adopted for convenience, and is truly artificial, at least, in its details. The classes alone may be arranged in a natural order, according to the degree of their complexity; and in this view two methods
may be pursued; one to ascend from the most simple to the most compound as M. Jussieu has done, or to descend from the compound to the simple, as the Zoologists do, and as Haller and La Marck have done in the vegetable kingdom. The question in itself, is of little importance, but it is, nevertheless, necessary to consider it for a moment.
“At the first view, nothing appears more philosophical, that to commence a series by the most simple beings, and to ascend by degrees to those whose structure is more complex. This course appears the more adapted to the vegetable kingdom, because we know or believe that we know more certainly which are the most simple vegetables, than which are the most complex.
“But if, we examine the question more attentively, above all, if we refer to experience, we find many inconveniences in commencing by the most simple vegetables. The most simple beings of each kingdom are the least perfectly known, and it is contrary to all the rules of logic
* Invariable, perhaps, in the genus, but not in the class.
to commence by objects less known, and advance to those that are more known. Thus may be remarked, that the course of botany in which the order indicated by the work of M. de Jussieu is followed, is very difficult to beginners. In fact, what is this pretended simplicity of certain beings? Do not all the beings of each kingdom exercise all the appointed functions of their existence ? All animals feel, move, nourish themselves, and propagate their species; all vegetables nourish themselves, grow, and propagate their species also. What real difference is there then between them? It is, that in one which we call complex, each function, each part of a function is performed by a distinct organ, whilst in others that we name simple, the organs little different from one another seem to execute in common all functions. But if this is the case, it is more easy to study and to know one of the beings of the first class than of the second ; this is exactly what experience confirms. When we know well the anatomy of the superior animals, we are only then capable of detecting the corresponding organs of the inferior animals; it is only after many of the mysteries of the fecundation of large vegetables have been discovered, that we are able to unravel some part of those of the acotyledonous plants.
“Since then, it is in itself altogether a matter of indifference, whether we begin the series by one extremity, or the other, I consider this as a case in which we may yield to the convenience of study, and arrange the vegetable kingdom on the same principle as the animal; beginning with the class the most complicated, that of the Dicotyledoneæ, and finishing by that which appears to be the least so, that of the Acotyledoner.”-Theor. Elem. pp. 334-236.
In pursuance of those views, the system of natural orders has been modelled by M. de Candolle. Beginning with those plants which appear to be most perfect, having many leaves or segments to the calyx, many petals to the corolla, many stamens and many styles—(the Polyandria Polygynia of Linnæus)—he passes gradually to those in which these organs become less numerous or disappear altogether.
To shew the great accessions which have recently been made to botany, it may be worth while to present our readers with a few notes from the “ Systema Naturale." In the first order, the Ranunculaceæ, Dioscorides noticed 25 species, Bauhin 86, Tournefort 126, Linnæus 130, Willdenow 217, Persoon 260, De Candolle 509. In the second order, the Dilleniaceæ, none were known even to Tournefort, 3 to Linnæus, 21 to Willdenow, 96 to De Candolle. To take a more common order, the Cruciferæ, 22 appear to have been known to the ancients, Bauhin knew 141, Tournefort 240, Linnæus 234, Willdenow 414, Persoon 504, De Candolle 900; and scarcely a season passes over in Europe, without announcing the appearance of new publications, adding many materials to the mass already collected; the return of some private adventurer bringing a rich tribute to the stores of natural history, or the arrival of some public expedition, laden with new discoveries.
Of the execution of this Prodromus, we need scarcely speak. It has been undertaken under every possible advantage, and every assistance which the improvements of the age could furnish, has been afforded. To accelerate the work, a few of the orders have been prepared by his friends and pupils, and revised by the author, but the great labour bas been performed by his own efforts. It would, no doubt, be easy in these three volumes to point out a few errors, some plants that have probably been repeated or misunderstood, many that are still omitted. But it was the arrangement and classification, that at present we proposed to consider, not its details. At a future day, if in our day this work shall be completed, we may examine its execution as far as our own country is concerned, or we may return to it on the appearance of its successive volumes. We consider it a great offering presented to the science of botany; a foundation on which future improvements and additions may be made with more facility, accuracy and certainty, than at any preceding period in its annals. Every student or friend of botany, must wish for its early completion.
ART. VIII.-Anne of Geierstein ; or the Maiden of the Mist. By
the Author of “Waverly.” 2 Vols. Reprinted at Philadelphia. Carey, Lea & Carey. 1829.
We congratulate the reading public, on the pleasure they have shared with us, in the perusal of tbis last production of the gifted author of " Waverly.” We join in right good will, in partaking the rich and tempting banquet which he has spread before them, and although, in our vocation of professed critics--whose very element is censure and dispraise—who subsist on the follies and defects of authors, we may be supposed to look with no peculiar favour, on works, whose overwhelming popularity and incomparable excellence, make criticism at once impotent and superfluous-yet, we ask, to be believed when we aver, that we find truer gratification in the enjoyment of such exquisite fare, as is here presented—than in the