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instances produces the effect by its sole action, also, unaided, produces the effect resultant from a double action.

Were such a law of affinities or attractions as I have suggested to regulate the external phenomena of creation, we might expect that, as we do in chemistry, so here we should find many affinities opposing each other, and that the attraction of the colour or appearance of the soil, or habitation of the species, would only be one of many elements by which the conditions of its form and appearance would be determined. This would meet an objection which might otherwise be raised against my suggestion-viz., that on many animals there is no indication, or at least no apparent indication, of an affinity in appearance to the character of the place in which they are found. True, the answer may be likened to that used by the phrenologists, who, when some man with all the good bumps commits an atrocious crime, explain the anomaly by telling us he had counteracting bad bumps. The answer, by force of association, rather approaches the ridiculous; we are inclined to look upon it as a quirky evasion, but this is owing to its misuse and exaggeration; in sober earnest, it is so only when misapplied. Every one of us, if we ask our own conscience, must admit that we have a constant fight going on between our good and our bad inclinations; and the same struggle between opposing qualities, between opposing habits, and opposing laws, is to be seen in every branch of science.

Should my view appear of a nature tending to throw light upon the phenomena of creation, I apprehend it will not be found of less weight if I go a little further, and offer to extend it to the phenomena of life (as in contradiction to the phenomena of creation). These are by no means the same thing. If applicable solely to the phenomena of creation, my suggestion might apply to all such cases of permanent similarity to the solum in quo as I have adduced; but could not, or at all events could only by a more complicated and indirect route, apply to cases of temporary or seasonal variation. No original law of attraction by similarity could regulate the appearance of the variable hare at its creation, because such attraction could only affect it once;

and if the hare were once created white or brown, its creation is over, and further change through that law at an end. But if we look upon the rule as subsisting not only at creation, but all through life, and as a great law or influence affecting life, then the subsequent changes of the hare from brown to white, and back again, are in accordance with it. The greater whiteness of all animals at the Poles is explainable; we perceive under what law the fish or the bird assumes the hue of its feeding-ground, although we remain in ignorance of the modus operandi of the law.

There is yet a further step, which the advocates of a modification of species might not hesitate to take-viz., to abandon the idea altogether as a law of creation, and confine it to a rule of life. Combined with a belief in the modification of species, it might help us to see how, through its influence, so far as outward appearance is concerned, an Alpine hare might become the Arctic species; how the desert locust might be derived from the common one; how a moth like a weatherbeaten, lichen-encrusted rock, should proceed from one from the woods, and so on. There may be truth in the idea that changes in species do arise from the modifications of climate, food, &c.; but I confess that, in the present state of my information on the subject, I am not inclined to look upon such instances as the above as cases where such modification has taken place, but rather as instances of the exercise of the original law I have assumed, or of some other such law of equivalent force and application; and would hold, that while such law may be exercised co-ordinately and simultaneously with one producing a certain amount of modification of species, it cannot be substituted for such modifying principle; still less can the instances of its operation be adduced as proofs of the existence of that principle.

As I have already said, the fact of a great family resemblance subsisting among all the creatures belonging to one continent and its dependencies, although not properly falling under the head disguise, must not be lost sight of in considering this question, and would seem to have a special bearing upon this phase of it. That such great regional resemblances exist, every naturalist knows. Contrast the deep and gloomy

Javanese forests, with their gorgeous epiphytes and poisonouslooking plants, with the fir-clad alpine scenery of Norwaythe arid plains of Africa with the beauty of our West Indian Islands-the strange Australian scrub with the Tartarian. steppes-and see how distinctive and marked is the general character of each; and not less marked in general effect than in individual detail. Show an experienced naturalist or botanist a new plant or animal, prating nothing of its whereabouts, and yet ten to one he will correctly tell the country from which it has come. There is an undefinable facies about them which enables the practised eye to allot to them their proper station, as the detective officer is said to be able to tell the felon, meet him in what company he may; and this family, or rather regional facies, extends around the particular country as the air of its climate envelopes it-as, for instance, in the Gallapago Islands, which lie nearest to America, although 500 or 600 miles distant from it, it is found that although the animals are for the most part distinct, they yet bear the American facies.

Now, although we find this regional character so well marked as I have stated, it stands to reason that all are not equally well defined. Where the contrast in climate and condition of life is great, the difference in organic productions is great likewise. The contrast is much greater between the fauna and flora of this country and West Africa than between those of this country and North America; and of course the converse is true likewise. Where the conditions of life are similar, the animal and vegetable products, although distinct, are found to be similar also. This gives rise to that most interesting class of plants and animals known as representative plants and animals.

But this is a word which is used with two significations, only one of which is properly applicable to my present inquiry. One kind of representative species (and that is the kind with which I am not at present dealing) is where a specific function is allotted to widely different species, in countries whose climate and conditions greatly differ. For example, the scavenger duty, which in cold countries is mostly performed by the burying beetles, is in tropical countries perNEW SERIES.-VOL. XI. NO. I.-JAN. 1860.

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formed by heteromerous beetles, a totally distinct tribe. These represent each other in their functions, although not in their form or character. The representative species with. which I have to deal are those which are found, in similar countries, replacing each other both in form and function. As in plants, the Cacti of South America replacing the Euphorbice of South Africa, the Epacris of Australia taking the place of the heath of the Cape, &c. ; in insects, the Eleodes of California taking the place of the Blaps of Siberia, the Eucrania of the deserts of Northern Patagonia replacing the Ateuchi of the deserts of the Old World; in reptiles, the crocodile of the Old World superseding the alligator in the New; in birds, the ostrich in Africa represented by the rhea in South America, and the emu in Australia; in mammals, the leopard represented by the jaguar, the camel by the llama, and so on.

Now, it is to be observed that this class of representative species is only to be met with when similar conditions of life exist in both countries. The ostrich, rhea, emu, for instance, find the climate and the extensive plains suited to their structure and mode of life, in all the three countries where they are found; they are not to be met with in mountainous countries; the prehensile tailed monkies, the agile squirrels, &c., are only to be found where there are trees; and so in every other instance. Would it not, then, appear that the general character or facies of the animals in different regions is the result of some special influence or condition in the country peculiar to each? and if we adopt this view, must it not follow as a corollary, that, where the conditions are the same, we should see the same facies appearing in each. Now, in point of fact, in those cases where the conditions approach to the same, we see enough to show it to be probable that it is so. I would go further, and say that there is good ground for holding that, were they really identical, we should see the same facies reappear. Let me illustrate this by two or three instances showing the effect of different degrees of nearness of condition. Compare the United States with Europe: the conditions are similar but distinct; so is the fauna. Compare the salt deserts of the Caspian with the salt deserts of the Mormons the conditions are here more similar; and recent

discoveries tell us that the facies of the fauna of these two countries is singularly alike. Compare the Gold Coast, Gabon, &c., and a portion of the coast of Mozambique. Among the Coleoptera, we find Goliaths in both, and many other species allied to species on the opposite side of the continent. They are not the same, but only belong to the same genera. Is this the result of intercommunication, and does it indicate the existence of a similar zoological belt extending across the country? It is mere conjecture to say, No; subsequent explorations must solve the question; but it seems in the last degree improbable that the climate of the coast should extend through the centre of the land. And, lastly, compare the fauna and flora of the Arctic regions of Europe, of Asia, and of America, where the conditions cease to be different, and we find that there there is no longer a separate facies-the type of all three is the same. The light in which I look upon these facts is, that where, in a similar latitude, we have similar conditions of existence, we have dependent upon and flowing from that similar zoological provinces, or separate, distinct, and isolated patches, having nothing whatever to do with each other, but, at the same time, possessing allied species; and this I maintain, not through intermixture of species, or by modification of species, or by the passage of the same species from one continent or one part of a continent to another, but by the same conditions of creation presenting themselves for the evolution of the creative idea. Of course, in saying this, I do not speak of identical species, which may have passed from one place to another by the ordinary means of migration or intercommunication. I speak of the general typical resemblance which we find in species distinct and peculiar to each region; and my idea is, that as close a general resemblance would have been found, although each of these regions of the continent of which I speak had been separated from each other by thousands of miles, irrespective of latitude and hemisphere (the same conditions, of course, existing in other respects).

In short, if we could find two countries exactly corresponding in every respect, however widely separate, I should expect to find, not, of course, the same species in both (for as we have dif ferent species in our own and every country, so we must expect

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