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were from passive habits; and that is the pouch of the pelican. The description which naturalists give of this organ, is as follows: “ From the lower edges of the underchap, hangs a bag, reaching from the whole length of the bill to the neck, which is said to be capable of containing fifteen quarts of water. This bag, the bird has a power of wrinkling up into the hollow of the underchap. When the bag is empty it is not seen : but when the bird has fished with success, it is incredible to what an extent it is often dilated. The first thing the pelican does in fishing, is to fill the bag; and then it returns to digest its burthen at leisure. The bird preys upon the large fishes, and hides them by dozens in its pouch. When the bill is opened to its widest extent, a person may run his head into the bird's mouth; and conceal it in this monstrous pouch, thus adapted for very singular purposes*.” Now this extraordinary conformation is nothing more, say our philosophers, than the result of habit; not of the habit or effort of a single pelican, or of a single race of pelicans, but of a habït perpetuated through a long series of generations. The pelican soon found the conveniency of reserving in its mouth, when
* Goldsmith, vol. vi. p. 52.
its appetite was glutted, the remainder of its prey, which is fish.
The fulness produced by this attempt, of course stretched the skin which lies between the under-chaps, as being the most yielding part of the mouth. Every distension increased the cavity. The original bird, and many generations which succeeded him, might find difficulty enough in making the pouch answer this purpose: but future pelicans, entering upon life with a pouch derived from their progenitors, of considerable capacity, would more readily accelerate its advance to perfection, by frequently pressing down the sac with the weight of fish which it might now be made to contain.
These, or of this kind, are the analogies relied
upon. Now, in the first place, the instances themselves are unauthenticated by testimony; and, in theory, to say the least of them, open to great objections. Who ever read of camels without bunches, or with bunches less than those with which they are at present usually formed? A bunch, not unlike the camel's, is found between the shoulders of the buffalo; of the origin of which it is impossible to give the account here given. In the second example ; Why should the application of water, which appears to promote and thicken the growth of feathers upon the
bodies and breasts of geese, and swans, and other water-fowls, have divested of this covering the thighs of cranes? The third instance, which appears to me as plausible as any
that can be produced, has this against it, that it is a singularity restricted to the species ; whereas, if it had its commencement in the cause and manner which have been assigned, the like conformation might be expected to take place in other birds, which fed
fish. How comes it to pass, that the pelican alone was the inventress, and her descendants the only inheritors of this curious resource?
But it is the less necessary to controvert the instances themselves as it is a straining of analogy beyond all limits of reason and credibility, to assert that birds, and beasts, and fish, with all their variety and complexity of organization, have been brought into their forms, and distinguished into their several kinds and natures, by the same process (even if that process could be demonstrated, or had it ever been actually noticed) as might seem to serve for the gradual generation of a camel's bunch, or a pelican's pouch.
The solution, when applied to the works of nature generally, is contradicted by many of the phænomena, and totally inadequate to others. The ligaments or strictures, by
which the tendons are tied down at the angles of the joints, could, by no possibility, be formed by the motion or exercise of the tendons themselves ; by any appetency exciting these parts into action; or by any tendency arising therefrom.
The tendency is all the other way; the conatus in constant opposition to them. : Length of time does not help the case at all, but the reverse. The valves also in the blood-vessels, could never be formed in the manner which our theorist proposes. The blood, in its right and natural course, has no tendency to form them. When obstructed or refluent, it has the contrary. These parts could not grow out of their use, though they had eternity to grow
in. The senses of animals appear to me altogether incapable of receiving the explanation of their origin which this theory affords, Including under the word “sense” the organ and the perception, we have no account of either. How will our philosopher get at vision, or make an eye? How should the blind animal affect sight, of which blind animals, we know, have neither conception nor desire ? Affecting it, by whať operation of its will, by what endeavour to see, could it so determine the fluids of its body, as to inchoate the formation of an eye? or, suppose
the eye form
ed, would the perception follow? The same of the other senses.
And this objection holds its force, ascribe what you will to the hand of time, to the power of habit, to changes
too slow to be observed by man, or brought within any comparison which he is able to make of past things with the present: concede what you please to these arbitrary and unattested suppositions, how will they help you? Here is no inception. No ws, no course, no powers of nature which prevail at present, nor any analogous to these, would give commencement to a new sense. And it is in vain to inquire, how that might proceed, which could never begin.
I think the senses to be the most inconsistent with the hypothesis before us, of any part of the animal frame. But other parts are sufficiently so. The solution does not apply to the parts of animals, which have little in them of motion. If we could
suppose joints and muscles to be gradually formed by action and exercise, what action or exercise could form a skull, or fill it with brains?? No effort of the animal could determine the clothing of its skin. What conatus could give prickles to the porcupine or hedgehog, or to the sheep its fleece?
In the last place; What do these appeten