It is upon this principle that I have constructed the natural arrangement which I am about to detail; and a single remark upon the arrangements adopted by the most celebrated modern physiologists, will, at once, shew the originality of the plan which I propose, and point out the errors of arrangement which I deprecate. Blumenbach, Chausier, Dumas and Bichat, treat of circulation before absorption, on which it depends, and even before mastication, deglutition and digestion, on which, in general, even absorption itself chiefly depends. If the arrangement of Chausier in particular, who, in this respect, is as accurate as any of them, were to be considered as indicating the relation and dependence of the functions, so absurd is it, that absorption instead of the cause, would be the result of nutrition, generation the result of absorption, and digestion the result of generation. Thus, by arranging effects in the place of causes, they confound the relations of the functions, and reverse the very order of their dependence. The division of the functions into external and internal, as anciently proposed by Aristotle, and afterwards successively adopted and improved by Buffon, Grimaud and Bichat (the last of whom substituted for them the terms organic and animal) is still more faulty. Anatomy, I divide into three parts, namely that which considers the mechanical or loco-motive organs, that which considers the vital organs, and that which considers the intellectual organs. Under the mechanical or loco-motive organs, I class, first, the bones which support the rest of the animal structure; second, the ligaments which unite them; and third, the muscles which move them. Under the vital organs, I class, first, the organs of digestion, the absorbent surfaces, and the vessels which absorb from these surfaces; second, the heart, lungs and blood-vessels, which derive their contents (the blood) from the absorbed lymph; and third, the organs of secretion, which separate various matters from the blood. Then follow the generative organs, which, though generally formed into a distinct class from the vital, ought not by any means to be so reckoned. For it is evident, that they form, as it were, the sequel of the vital organs, being dependent on secretion—the last of the vital functions, and destined merely to propagate vitality, and to communicate it to a new series of beings. Under the intellectual organs, I class, first, the organs of sense, where impressions take place; second, the brain or organ of judgment, where these excite ideas; and third, the nerves, where volition results from the last. This is a natural arrangement of the anatomy of animals, and its peculiar simplicity is illustrated by its involving, in application, that of minerals and vegetables, and by its being capable of instant adaption to physiological science.