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ILLUSTRATIONS OF INDIAN BOTANY.

sible qualities, the Ranunculaceae have many structural affinities ; their numerous carpels, the number of their floral divisions, indefinite stamens, and the analogous habit observed in many species of both orders, all indicate this relationship; but, they are at once distinguished by the petals and stamens in Rosaceae, being inserted on the calyx, or perigynous, while in Ranunculaceae, they are both inserted under the ovaries, or, hypogynous.

Many other analogies might be indicated, but enough has been said to show the absolute necessity of attending to every point of structure in determining the order of any plant under examination, for, the order once ascertained, it is in general a comparatively easy task to make out the genus: one, and not the least of the advantages which the natural method possesses over the artificial, or sexual, system; as in it, a glance often serves to ascertain the class and order of a plant, but leaves the difficulty of determining the genus little of all diminished, while in all cases of departure from the regular form, such as the addition or suppression of a stamen or pistil, not a very rare occurrence, the Botanist unacquainted with the laws which give rise to, and regulate these metamorphoses, has no guide to direct him, where else in the system, to look for the plant under investigation. With the view therefore of facilitating the determination of orders, I shall usually append a summary of the essential characters of each; promising, however that these summaries must be received with considerable latitude, as it is often impossible to compress within a few words even the leading characters only : but they may serve as helps, by directing attention to those points of structure which are considered essential to the order.

Essential Character. Flowers polypetalous, polyandrous, ovaries wholly superior: leaves without stipules : seeds without an aril, with copious fleshy albumen. A few have definite stamens, and Clematis, Thalictrum, and some others, are without petals; but agree in all other respects with the characters indicated.

Geographical Distribution. As already stated, this considering its great extent, in a remarkable degree an extra-tropical order. A few only are found in India within the 25° of North Latitude, and these, with the exception of 8 or 9 species, are confined to the temperate climate of the higher hills, thus affording a striking instance of analogous organization and habit, pervading nearly the whole of an extensive family of plants, and an instructive example of the effect of these in determining the geographical distribution of its species, showing in another and very favourable point of view, the advantage we derive from studying plants according to this method, since, by enabling us to generalize our isolated observations on the structure, habits, and peculiarities of individual plants, it suggests their extension to whole families, and teaches us how we may by studying carefully the peculiarities of a single species, learn by analogy those of a whole order, a sort of alebriacal method, if I may so express myself, of studying vegetable physiology, which has within the last few years led to many most important discoveries in that science, To show that this is no hypothetical statement it is only necessary to adduce the fact, that the generally received division of the vegetable kingdom into three great classes, Acotyledons, Monocotyledons, and Dicotyledons, has become so simplified in its application to practice, that it is no longer necessary in determining to what class plant belongs to undertake the often difficult and delicate operation of dissecting the seed, since its structure is generally indicated by such palpable differences in the formation of the stem and leaves as render the most cursory inspection of those parts sufficient to determine the class to which the plant belongs. It would certainly be going too far out of my way to enter upon the examination of these distinctions here, suffice therefore to state, that such is the case, and that a reference to any of the recently published Introductions to Botany, or to the concluding pages of the preface of my Prodromus,*[1] will furnish an exposition of, the observations on

which the principles are based. But to return from this digression. Twelve out of fifteen species known to me as indigenous in this peninsula, are only found on the higher hills, the remaining three, which are all twining shrubs, are met with on both hills and plains, but more frequently on the former than the latter. One of them, Climatis Gourrana, which I frequently met with in Mysore, appears admirably suited, from the profusion of its fine clusters of flowers, for the formation of arbours in the manner some of its congenus are employed in Europe. Of the

  1. * Prodromus Florae Penins. Ind. Oriental.