Page:Aristotle - History of Animals, 1883.djvu/28

2 sometimes in number more or less, or in size greater and smaller, or in any quality which can be included in excess or defect. For some animals have a soft skin, in others the skin is shelly; some have a long bill, as cranes, others a short one; some have many feathers, others very few; some also have parts which are wanting in others for some species have spurs, others have none; some have a crest, others have not. But, so to say, their principal parts and those which form the bulk of their body, are either the same, or vary only in their opposites, and in excess and defect.