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tain-shaped prominence for the articulation, a certain relation between the position of the resisting power and that of the strength employed with the fulcrum; a certain volume in the temporal muscle, requiring an equivalent extent in the hollow which receives it, and a certain conyexity of the zygomatic arch under which it passes ; this zygomatic arch must also possess a certain strength to give strength to the masseter muscle.
That an animal may carry off his prey a certain strength is requisite in the muscles which raise the head; whence results a determinate formation in the vertebræ or the muscles attached, and in the occiput where they are inserted. ,
• That the teeth may cut the flesh they must be sharp; and they must be more or less so according as they will have, more or less exclusively, flesh to cut. Their roots should be more solid as they have more and larger bones to break. All these circumstances will, in like manner, influence the development of those parts which serve to move the jaw.
That the claws may seize the prey they must have a certain mobility in the talons, a certain strength in the nails, whence will result determinate formations in all the claws, and the necessary distribution of muscles and tendons : it will be necessary that the forearm have a certain facility of turning, whence again will result determinate formation in the bones which compose it; but the bones of the forearm articulating in the shoulder-bone cannot change its structure without this latter also changes. . . . .
'In a word, the formation of the tooth bespeaks the structure of the articulation of the jaw; that of the scapula indicates that of the claws; just as the equation of a curve involves all its properties ; and in taking each property separately, as the basis of a particular equation, we should
find again both the ordinary equation and all the other certain properties ; so, the claw, the scapula, the articulation of the jaw, the thigh-bone, and all the other bones, separately considered, require the certain tooth, or the tooth requires them reciprocally; and, beginning with any one, he who possessed a knowledge of the laws of organic economy would detect the whole animal.
We see, for instance, very plainly, that hoofed animals must all be herbivorous, since they have no means of seizing on their prey. We see, also, that having no further use for their forefeet than to support their bodies, they have no occasion for so powerfully-framed a shoulder; whence we may account for the absence of the clavicle and acromion, and the straightness of the scapula. Not having any occasion to turn their foreleg, their radius will be solidly united to their ulna, or, at least, articulated by a hinge-joint, and not by a ball and socket, with the humerus. Their herbaceous diet will require teeth with a broad surface to crush seeds and herbs; this breadth must be irregular, and for this reason the enamel parts must alternate with the osseous parts. This sort of surface compelling horizontal motion, or the grinding of the food to pieces, the articulation of the jaw cannot form a hinge so close as in carnivorous animals: it must be flattened, and correspond with the facing of the temporal bones, more or less flattened. This temporal cavity will only contain a very small muscle,—will be small and shallow.
We have no difficulty, then, in understanding that an animal is a complete machine, with harmonies and correspondent provisions in every part of its organization : that the whole creature, in the integrity of its being, recognizes its own character, and executes its own will by the concur
rent aid and perfect agreement of every distinct portion of its body: that there is nothing empirical in its structure, nothing mutable or fluctuating in its system; and that no change, in the true meaning of change, could take place in any of its parts without impairing the whole, which is perfect in the consentaneous perfection of all its members, directed to one object and operating with one aim, to fulfil the preordained destinies of the animal's life.'
Every animal that exists is, for the purposes of its existence, as perfect as it can be ; and is as far out of the reach of ideal improvement, and beneficial changes in a slight degree,' as the sun itself, whose light and heat sustain the existence of every organic being.
THE ARGUMENT OF DESIGN.
AFTER these multiplied considerations of the Theory before us, we approach the concluding question which involves the whole argument, is there a design in the existence of plants and animals ? Have they been brought into being for a special purpose according to a preconceived plan? or is their appearance the uninfluenced result of circum. stances, and a natural sequence of events without any speci. fic design or particular object ?
The Theory of course denies any idea of design, and that too in precise words, as well as in the general discussion; and, in this respect, whenever the question seems to incline towards the notion of creation, it is uniform in its statements. Mr Darwin has carefully considered all the vulner, able parts of his Theory in the presence of a creative design, and has guarded them from that quarter where danger is most apparent, to the best of his abilities. Nevertheless, the Theory is not invulnerable, for as the heel of the infant Achilles was covered by his mother's hand when she plunged him in the waters of Lethe, so this Theory has not, in every portion, been thoroughly imbued with Atheism, as its parent has kept one little spot untouched-the breathing of life into the primordial spore—an exception which leaves the whole theory open to a death-wound.
But though Mr Darwin, with this one exception, which he apparently could not avoid, has been so watchful in warding off creation ; he has without scruple admitted a designing and contriving power of his own invention, which he invests with the most marked attributes of the creator, and in such large terms as he would certainly consider superstitious and credulous if applied to the interposition of a Divine Power. We have seen a good deal of this already, we shall see more of it presently.
But truly he must be a courageous man who can contemplate all the forms of life in this our globe, all the structure of animals and plants, all the habits of different animals and the parts they sustain in Nature, and all the vast variety of their tribes constituted to enjoy life in certain special climates, removed from which they* could not live,
• We must suppose that when the author of nature creates an animal or a plant, all the possible circumstances in which its descendants are destined to live are foreseen, and that an organization is conferred upon it which will enable the species to perpetuate itself, and survive under all the varying circumstances to which it inust be inevitably exposed. Now the range of variation of circumstances will differ essentially in almost every case. Let us take, for example, any one of the most influential conditions of existence, such as temperature. In some extensive districts dear the equator, the thermometer might never vary through several thousand centuries, for more than 20° Fahrenheit; so that if a plant or animal be provided with an organization fitting it to endure such a range, it may continue on the globe for that immense period, although every individual might be liable at once to be cut off by the least possible excess of heat or cold beyond the determinate degree. But if a species be placed in one of the temperate zones, and have a constitution conferred on it capable of supporting a similar range of temperature only, it will inevitably perish before a single year has passed away.'—Principles of Geology, ii. p. 351, 3rd edition,
These sentiments it is to be presumed Sir Charles Lyell must now repu. diate, under the influence of the Lamarckian system of which he has be. coine the advocate. If he is faithful to his new creed, the creator and the plan of creation must of necessity be repudiated.