In two different parts of his treatise on animals, Aristotle states that the lioness produces five or six whelps at her first litter, four or five at the second, three or four at the third, two or three at the fourth, and one or two at the fifth, and after which she becomes barren. This assertion is ungrounded, since in all animals the first and last litters are always the least numerous. This philosopher erred also, as well as all the naturalists that came after him, in maintaining that the lioness had but two nipples, it being a certain and well known fact that she has four, as may be known by simple inspection. He likewise asserts that the lion, bear, and fox, are unformed at their birth; but it is now known that these animals are brought forth as perfect as any other, and that their members are distinct and developed. He says too that the lions copulate in a backward disposition; but from a bare inspection it is demonstrable that they engender in the same manner as other quadrupeds. I have noticed these errors in Aristotle minutely, as the authority of such a great man has misled all authors who have since given the history of animals. His assertion also, that the neck of the lion contains but one rigid and inflexible bone, has been contradicted by experience; for in all quadrupeds, without exception, and even in man, the neck is composed of seven vertebræ; and it is also another certain fact, that in general, carnivorous animals have a much shorter neck than granivorous, and especially than the ruminating ones. It is also stated by Aristotle, that the bones of lions have neither cavity nor marrow; that they are as hard as flint, and possess the property of striking fire by friction; but such errors ought not to have been repeated by Kolbe, nor handed down to posterity, since even in the days of Aristotle they were ridiculed by Epicurus.