Page:The Works of William Harvey (part 1 of 2).djvu/436

 material which is also various in its nature, and variously dis- tributed, and such as is now adapted to the formation of one part, now of another ; on which account we believe the perfect hen's-egg to be constituted of various parts.

Now it appears clear from my history, that the generation of the chick from the egg is the result of epigenesis, rather than of metamorphosis, and that all its parts are not fashioned simultaneously, but emerge in their due succession and order ; it appears, too, that its form proceeds simultaneously with its growth, and its growth with its form ; also that the generation of some parts supervenes on others previously existing, from which they become distinct ; lastly, that its origin, growth, and consummation are brought about by the method of nutrition ; and that at length the foetus is thus produced. For the for- mative faculty of the chick rather acquires and prepares its own material for itself than only finds it when prepared, and the chick seems to be formed and to receive its growth from no other than itself. And, as all things receive their growth from the same power by which they are created, so likewise should we believe, that by the same power by which the chick is pre- served, and caused to grow from the commencement, (whether that may have been the soul or a faculty of the soul,) by that power, I say, is it also created. For the same efficient and conservative faculty is found in the egg as in the chick ; and of the same material of which it constitutes the first particle of the chick, out of the very same does it nourish, increase, and superadd all the other parts. Lastly, in generation by meta- morphosis the whole is distributed and separated into parts ; but in that by epigenesis the whole is put together out of parts in a certain order, and constituted from them.

Wherefore Fabricius was in error when he looked for the material of the chick, (as a distinct part of the egg, from which its body was formed,) as if the chick were created by meta- morphosis, or a transformation of the material in mass; and as if all, oj at least the principal parts of the body sprang from the same material, and, to use his own words, were incorporated simultaneously. [He is, therefore, of course opposed to the notion] of the chick being formed by epigenesis, in which a certain order is observed according to the dignity and the use of parts, where at first a small foundation is, as it were, laid,