They even knew, and have described several species of Glires of inconsiderable size, when these animals presented any thing remarkable in their conformation or properties[61]. But the small species are of no importance with reference to the object in view; and, it is sufficient for our purpose to have shewn, that all the large species, which possess any remarkable character, and which we know to inhabit Europe, Asia, and Africa, at the present day, were known to the ancients; whence we may fairly conclude, that their silence in respect to the small quadrupeds, and their neglect in distinguishing the species which very nearly resemble each other, as the various species of antelopes, and of some other genera, were occasioned by want of attention and ignorance of methodical arrangement, rather than by any difficulty proceeding from climate. We may also conclude, with equal certainty, that, as the lapse of eighteen or twenty centuries, together with the advantages of circumnavigating Africa, and of penetrating into India, have added nothing in this department to the information left us by the ancients, there is no probability that succeeding ages will add much to the knowledge of our posterity. But perhaps some persons may be disposed to employ an opposite train of argument, and to allege that the ancients were not only acquainted with as many large quadrupeds as we are, as has already been shewn, but that they have described several others which we do not now know,--that we act rashly in considering these animals as fabulous,--that we ought to search for them before concluding that we have exhausted the history of the present animal creation,--and, in fine, that among those animals which we presume to be fabulous, we may, perhaps, discover, when we become better acquainted with them, the originals of those bones of unknown animals which we discover buried in the earth. Some may even conceive, that those various monsters, which constitute the essential ornaments of the history of the heroic ages of almost all countries, are precisely those very species which it was necessary to destroy, in order to allow the establishment of civilization. Thus the Theseuses and Bellerophons of ancient times had been more fortunate than all the nations of our days, which have only been able to drive back the noxious animals, but have never yet succeeded in exterminating a single species. _Inquiry respecting the Fabulous Animals of the Ancients._ It is easy to reply to the foregoing objection, by examining the descriptions of these unknown beings, and by inquiring into their origins. The greater number of them have an origin purely mythological, and of this origin their descriptions bear unequivocal marks; for in almost all of them we see merely parts of known animals united by an unbridled imagination, and in contradiction to all the laws of nature.