The shoot grows, and becomes a twig, that is to say, the adolescent of the vegetable kingdom, with the ardour and the energy of the young among herbaceous creatures.

In this state the plant has already renewed its substance several times, and nothing remains of the organic and mineral elements which existed in the different beings that have preceded it on the same little corner of the earth which have witnessed the changing phases of its curious metamorphoses. Wait a while, and you will see the twig growing long and large. Its respiration becomes active, its leaves spread out, and vigorously exhale the carbonic acid gas of the air. The exhalation of watery vapour over all the surface takes place, and a young and vigorous tree is there, which day by day grows more robust and more beautiful.

During this growth, during this transition from the shrub to the young tree, with a separate and upright stem, a new being has been formed. Organs which it had not have come to it, and have made it a separate individual. It has flowers, it has branches, it has new vessels for the circulation of the sap, and the juices which were not previously elaborated. The structure of the surface of its leaves has been changed, so that absorption may be more successfully accomplished.

Where is the shoot, from which our vigorous young shrub sprung? What relation, what resemblance is there between these two beings? We can only discern differences. One individual has succeeded to another individual. The vegetable has been renewed, not only in matter, which is changed, but in the form of its organs. A series of new forms have succeeded each other in the shrub, since it was a simple shoot, just peeping above the soil.

It is still the history of change, when the young tree has become adult, when, in the progress of years, its trunk has grown hard, and become incrusted with layers of accumulated bark, when its branches have multiplied, and flowering and fruitage have modified all its internal and external parts. It is then a grand cedar tree, whose majestic and imposing shade covers a considerable extent of the soil; or a superb oak, whose robust and gnarled branches spread far and wide; or a flexible chestnut, which flings about its polished and shining arms. The organs of these luxuriant vegetables, the pride of our forests, have no relation to those which belonged to them in the first years of their life. Their flowery crowns in spring-tide, the fruits which succeed to them, the seeds shut up in the protecting shelter of those fruits, these are all peculiarities of organization, belonging to these noble trees, without any analogy in nature.

Where is the grain of mustard seed which formerly sucked the juice of the earth in darkness? Everything is changed; the place of habitation, which is no longer the earth, but the air; the form, and the physiological functions. Not only has all this changed, but it has changed a great number of times. Not only does nothing remain of the matter of which the tree was composed in the earlier stages of its life, but nothing has been retained of the organic forms which were proper to the infancy of the vegetable.

Nevertheless, O great mystery of Nature, in the midst of all these changes, notwithstanding this continual succession of beings, which mutually replace each other, there is something which remains immovable, which has never changed, which has preserved a constant individuality,—it is the secret force which produced all these changes, which presided over all these organic mutations. In our belief, this force is the animated germ which the young plant has received from the seed, whence it has proceeded. In the midst of all the transformations which the vegetable creature has undergone, in spite of the numerous phases through which it has passed, and which have produced a series of different beings succeeding each other in its material substance, the spiritual principle, cause and agent of all this long activity, has remained the same. This animated germ which now exists in the adult vegetable is the same which was there during its growth, the same which was there when it was a shoot, the same which slept in the seed which was thrown into the bosom of the cold and humid earth. In that majestic tree which, coming forth from an imperceptibly minute seed, has had a whole genealogy of successive beings, replacing each other, differing in form and size, and has preserved, throughout its incessant development, the sole and immutable principle of its activity, we behold the faithful image of the persistent, indestructible soul, in the midst of the beings or different bodies which it has animated in succession. Issuing from a germ, it has never ceased to grow, to develop, to become amplified, still remaining itself.

The grain of mustard seed, or the seed of the tree, is according to us, the plant or inferior animal into which the sun has thrown the animated germ. The subterranean plantlet corresponds to the animal whose mission it is to perfect the germ transmitted by the plant, and which develops and amplifies this germ; for example, to the fish or the reptile, perfecting the spiritual principle which they have received from the zoophyte or the mollusc. The shoot which, having burst out of the earth, grows in the shade of the grass, and tries its air organs, corresponds to the animal somewhat more elevated in the organic scale, such as the bird, in which the animating principle—derived from the reptile or the fish—increases in intellectual power. The young vegetable, arrived at the condition of the twig, which lives a completely aërial life, corresponds to the mammifer. The tree, grown tall, and pushing out its young boughs, corresponds to man, perfecting the soul which he has received from a mammifer. Finally, the powerful and vigorous forest lord, over-topping all the neighbouring trees in size and majesty, with mighty girth of stem, and noble crest, with wide-spreading branches and splendid flowers, this grand creature corresponds to the superhuman being who lives in the bosom of the ethereal fluid, and who is himself destined to be replaced by a series of superior creatures, who shall climb from stage to stage, from height to height, even to the radiant kingdom of the sun, where those absolutely spiritual beings, whose essence is entire and perfect immateriality are enthroned.

Thus, the animating principle remains immutable and identical with itself, during all the transformations undergone by the beings who are successively charged to receive this precious deposit. From the vegetable, in which it had its first domicile as a germ, and through the whole series of living creatures, from the plant and the zoophyte to the man and the superhuman being, the same spiritual principle is preserved in its identity, perfecting and amplifying itself without cessation.

Let us complete the comparison. When the forest tree has ripened its fruits, the fruits burst open, the seeds escape from it, and fall into the soil, or are dispersed by the caprice of the winds. If the seeds fall into damp earth, they germinate, and, according to the laws of nature, young vegetables are produced, as we have previously explained. Multitudes of similar vegetables are produced by a single oak, a single cedar, a single chestnut tree. Just as the majestic adult tree lets fall from its thousand branches upon the soil the countless seeds which are to germinate there, so the spiritualized beings who dwell in the sun shed their emanations, their animated germs, upon all the planets. These germs, carried to the earth by the sunbeams, and falling upon our globe, produce the vegetables which afterwards give birth to the various animals, by the effect of the successive transmigrations of the same soul into the bodies of these creatures.