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influence or power of its system to the anterior circumference of its body, it would gradually cause the extension or prolongation of some projecting points, until feelers, such as these animals now possess, should be insensibly but perfectly formed. In like manner, different organs have been fashioned for different animals, as their original outline or imperfect structure rendered necessary, and the accessions and variations to the form of each individual or race, have been transmitted to its posterity.
This theory is in many points visionary, in some incongruous if not absurd. It would be difficult, even on its own principles, to account for much of the peculiar organization which the study of natural history discloses; or to assign final or operating causes sufficiently powerful for the production of many of the anomalous forms which the vegetable and animal kingdoms abundantly exhibit. We know not why there should be so much symmetry in each individual form, or why a few general plans should be made to comprehend all existing beings, while the species which are embraced in each plan, which may be said to surround each system of life, vary in almost endless diversity, but still preserve the fundamental arrangements of the system to which they belong. We find order where we would have expected inextricable confusion. And often we find organs so imperfect, that we might suppose this great work of progressive amelioration had been at some period suddenly arrested. We might for instance, inquire why, of the testaceous molluscæ, some of which have been adduced by La Marck as illustrations of his theory, should only a portion have acquired feelers? Has the age of the world not yet been sufficiently protracted-or why should not these feelers, which have been acquired in their march of improvement, have gradually been divided and thus fashioned into hands, and, finally, rendered capable not only of touching but of holding any object, facilitating by this means not only the acquisition of food, but the movements of the animal itself. If this power really belongs to life, to spontaneous life, it is surprising that so many of the inferior orders of the animal kingdom should remain condemned to a stationary and almost vegetative existence. Strange that there should have been a pause in this march of voluntary creation ; a suspension of this power of progressive organization.
More powerful objections still occur. This progression of organization has apparently ceased, and we know not when or by what law it has been limited. If animals, furnished with the simplest rudiments of organization, have had power to multiply and complicate those rudiments; if the weakest combination of organs have had energy enough to strengthen and
increase their structure, why should not the complex extend their combinations, why should not the strong acquire new powers? If the imperfect molluscæ by their continued desires and efforts to move and touch surrounding objects, could form new organs, why cannot more perfect man add to his stature or improve his structure? If the aspirations of an individual, or the efforts of numbers could avail, many, besides Dædalus, would have endeavoured to annex to their frames the pinions of a bird. And on the coasts of Ceylon and Coromandel, where occupations are hereditary and permanent, and where families, perhaps tribes, have for upwards of three thousand years pursued, from father to son, the avocation of fishers of pearl; when the pursuits, the wealth, the anxious desires of these people all lay beneath the waves, surely in this long term of years, some races might have acquired some portions of the organization of the fish.
Even this, however, is an imperfect view of this question. If every organized body had advanced in the scale of organization to a somewhat equal degree; if all, though moving in different directions, had reached the circumference, the common boundary of some great circle, it might be supposed, that while the power of progressive organization had been granted as an attribute of life, and each individual or race been left to determine by accident the extension and direction of his own organs, there had yet been placed, from causes inscrutable to us, some limit to the progress, some ultimate term to the improvement of or ganized life.
But such has not been the history or the march of creation. We discover, even now, forms as imperfect, structure as incomplete, organization as simple as could apparently ever have existed. From the Monas Termes, the point where voluntary motion and life appear to our view to commence, the lowest term in our scale of sentient being, to man himself, we perceive the intermediate degrees occupied by a vast variety of forms, by almost unappreciable grades of organized substances, and yet in all of these substances or beings, this power of progressive organization, has long been suspended. It is upwards of three thousand years since accurate descriptions of some portions of the animal kingdom have been transmitted to us, and in that time, none of those objects which have been described, have undergone mutation. The camel and the horse are now as in the days of the patriarchs. Can the leopard change his spots? was asked many ages ago, and the leopard has not yet changed his spots, nor the Ethiopian his skin. And yet it may be remarked, that peculiarities of colour are among the most variable and fugitive properties of organized bodies.
There was a period, whilst science was yet undisciplined, when the minute microscopic animals were supposed to afford a strong support to this doctrine. They were asserted by many and admitted by more to be the products of an unintelligible spontaneous generation, the offspring of heat, of moisture, of the fermentation of elements endued with vitality, or of causes still more obscure. But in proportion as these bodies have been examined, under the guidance of an accurate and cautious philosophy, the darkness which overhung their origin has been dissipated. Forms the most minute, animals visible only under the lens of a compound or solar microscope, are found to have their structure as complete, the laws of their production as definite, their metamorphoses as regular as those of organized bodies, apparently the most perfect. Knowledge has swept away most of these illusions among the errors of unenlightened ages, and although myriads of animated beings are so minute as to elude the power and observation of our most perfect instruments, shall we not conclude that the plan, the system, which governs so beautifully, so uniformly, the kingdom of the living until our scrutiny ceases, because the eye fails us, must, on every principle of analogy, extend also to those far confines of nature that are to us invisible.
These opinions have, in some measure, been supported by the fact that animal or vegetable substances hermetically inclosed, and then subjected to degrees of cold or heat, sufficient to destroy, according to our observations, every germinating principle, every vestige of life, have yet been found after some time to contain living forms in wonderful abundance. Many solutions, however, may be given to this difficulty. We, ourselves, see imperfectly. Our powers of vision and of observation are very limited, and in our experiments, we are attempting to exclude by the coarse materials adapted to our senses and our instruments, beings to whom the most compact metals may appear like open net-work, and the diamond as porous as a honey-comb. Besides, we may miscalculate the power of heat or cold on life, because to some grades they are found pernicious. For when we perceive how wonderfully the Creator has prepared the races that surround us to live in differing elements, in air, in water, in the earth; how can we limit his power or his beneficence, how avoid the conclusion that forms might be fashioned to breathe even the pure ether of the empyrean space, or bask in the unclouded blaze of elemental fire ?
One fact, however, connected with this discussion, we cannot omit to notice. When we examine the now existing forms, and compare them with the remains of the extinct races which are
still so perfectly preserved, it becomes obvious that there have been successive creations. Most, perhaps all of the earliest inhabitants of our earth have perished, and new races have been called into existence to replace their loss, or, probably, to meet the varying temperature and the revolutions of the globe itself. The earth at different periods must have been accommodated to different inhabitants. The earliest races whose vestiges remain were all aquatic, living in an ocean which appears to have covered for ages the loftiest mountains of our globe-or we must suppose that the islands and continents of the present day were once located beneath the waves of the ocean, and have been raised by some deep-seated convulsion to their present elevation. The days of creation were of long and indefinite duration. If the present tribes of the animal kingdom had been formed contemporaneously with the earliest dwellers on the earth, some of their remains would even now be discovered in the more ancient strata, intermingled with the myriads of animals whose exuviæ are there embodied, and would not be confined to the more recent of the tertiary and alluvial soils.
May not the structure of animals in the course of ages have been greatly changed? We reply that the same arguments which oppose the doctrines of spontaneous generation or progressive organization apply with full force against any important variations in structure. Observation, experience, philosophy, all lead us to conclude that the forms now presented to our view, are the authentic forms of creation. They may be modified in that slight degree in which each species is accustomed, and almost constantly observed to vary. Generic forms have, perhaps, at first been created, specific differences and varieties have in the lapse of ages been produced by modifications of the same given organs, not by the formation of new
We are permitted to examine now the same forms which were declared to be good so many ages ago. proceed to study the great living book of nature, under a strong persuasion that we are studying the permanent and enduring forms of creation, not the varying, the inconsequential results of chance and accident.
It is in this vast domain of life, that the order established by divine wisdom, is so singularly conspicuous. We perceive beings almost innumerable, forms endless in their variety, creatures infinitely diversified in their habits and their pursuits, all submitting to the guidance and governance of a few simple universal laws. All, however varied may be their operations, instinctively labour for the preservation of their own lives and
the protection of their future progeny. The butterfly, which sports in the air, and files from plant to plant on wings as light and brilliant as the flower over which it hovers; wherever she herself may feed, yet deposits her eggs only on those plants which are the appropriate food of her infant caterpillar; the bee and the wasp consume their lives in building cells, and in depositing in those cells honey or insects, or some other food adapted to the support of that offspring they will never know; fish leave the ocean, struggle against the currents, ascend the rapids, leap up the falls of long rivers to deposit their eggs in places which the parent cannot inhabit, but where their young may find security and food--all bend to some paramount impression—all yield an unqualified obedience to the laws of their instinctive lives. These laws operate with unceasing forcethey are permanent and unchangeable. They have governed the living tribes of nature since their existence began; they will control them while their races exist. Chance can have no agency in principles so stable and so uniform.
One being alone has been liberated in part from this blind and uncontrollable instinct, has been permitted to compare causes and effects, to know good from evil. To one has been given the awful responsibility of free-will-and instead of the mysterious and unerring impulses of instinct, he has been endowed with that reason which must be his pride or his reproach. Man himself, is, perhaps, the most wonderful anomaly in the system of life; and while he avails himself of his privilege to examine all that surrounds him, all that now exists, and all that has been created, it should be a part of the same study cautiously to investigate his own position, to ascertain his connexion with the past, with the present, and with the future.
Availing ourselves of the researches of our predecessors and our contemporaries, we have presented in the narrow limits which the nature of our publication prescribes, some of those general and important views of nature which genius and science have unfolded to man. But we have not entered into the history of individuals, nor alluded to the systems which have been proposed for the arrangement of the organic and inorganic substances which are scattered over the globe; because of these and of the systems which may hereafter, from time to time, be promulgated, we shall, in the course of our labours, be frequently compelled to speak.