This argument, furnished by comparative anatomy, to show that man and the fossil animals could not have been contemporaries, will probably seem to have little force to those who are not familiar with the history of organic life on the globe, and the distribution of species. It is not generally known that both animals and plants are usually confined to a particular district, and that a removal beyond its boundaries, or the access of a few more degrees of cold, or heat, than is common in the place assigned them by nature, will destroy them. To him who understands this curious history, the argument under consideration is perfectly satisfactory, to prove the existence and consequent dissolution of myriads of living beings, anterior to man. "Judging by these indications of the habits of the animals," says the distinguished anatomist, Sir Charles Bell, "we acquire a knowledge of the condition of the earth during their period of existence; that it was suited at one time to the scaly tribe of the lacertae, with languid motion; at another, to animals of higher organization, with more varied and lively habits; and finally, we learn that at any period previous to man's creation, the surface of the earth would have been unsuitable to him. Any other hypothesis than that of a new creation of animals, suited to the successive changes in the inorganic matter of the globe, the condition of the water, atmosphere, and temperature, brings with it only an accumulation of difficulties."--_The Hand, its Mech._, &c. pp. 31 and 115. But when arguing with those who do not feel the force of this argument, I would fall back upon that derived from the fact, that of the ten thousand species of animals dug out of the rocks beneath alluvium, no relic of man has been found; and ask them whether they can explain such a fact, except by the supposition that man was not their contemporary.