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.