entirely different from the former, but in a continually progressive transformation of the original types, a succession of metamorphoses, on the nature of which we have received the most interesting information in he excellent observations of Goethe[1]. It appears that while the first rough type, as it were, of the whole plant is contained in the coatings or leaves of the seed (cotyledons), which abound with a gross and yet unelaborated sap; the same type is manifested more plainly in the successive divisions of the stem (internodia), and in the leaves, in which, when we compare the upper with the lower leaves which surround the stem, its progressive improvement becomes very distinctly evident. As soon as the plant has formed its leaves, which perform the functions of the organs of respiration and secretion, and has thus purified its fluids, it goes on to produce the flower, which is its most complete organ, entirely under the influence of the light. Even this transition is not performed suddenly, but is prepared by the formation of the calyx, wherein the leaves of the stem begin to contract themselves, while they unite in greater numbers around a common axis in the same plane: this formation shows itself most evidently in the collective calyx of flowers belonging to the class Syngenesia, in which the pappus performs the function of the calyx of single flowers. Moreover, the calyx itself constitutes the most evident transition to the corolla, the functions of which it often performs; and the corolla is only a finer calyx for the organs of generation, which, as the most compact and perfect organs, issue forth from their last organ of development and preparation, as from a covering which they have last thrown aside. It is a remarkable fact, and one which places the correctness of these views beyond doubt, that too rich a nourishment, and the accumulation of too many fluids not yet properly purified, may cause a retrograde organization of these parts; the organs of generation may be transformed into flower-leaves (as in double flowers), the leaves of the calyx may be changed back again into leaves of the stem (as is often the case in the calyx of the rose), and instead of the organs of generation, a new shoot or internodium, bearing a new flower, may appear (as in the proliferous roses or Rose-kings[2]). When, after such successive progression, the plant has reached the highest point of polarity between root and flower (gravitation and light), between which the stem and leaves may be considered as mere connecting links, similar in their function to that of the epidermis between the cellular system and the system of the spiral vessels, the same opposition appears once more under the form of male and female stamina; the latter of which, as containing the germ of a new plant (the seed), belong more to the reproductive system, and stand more under the influence of the earth. Wherefore the inferior plants, such as
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DR. CARUS ON THE KINGDOMS OF NATURE.
