wood, or a statuary his statue from a block of marble. For out of the same material from which the first part of the chick or its smallest particle springs, from the very same is the whole chick born; whence the first little drop of blood, thence also proceeds its whole mass by means of generation in the egg ; nor is there any difference between the elements which constitute and form the limbs or organs of the body, and those out of which all their similar parts, to wit, the skin, the flesh, veins, membranes, nerves, cartilages, and bones, derive their origin. For the part which was at first soft and fleshy, after- wards, in the course of its growth, and without any change in the matter of nutrition, becomes a nerve, a ligament, a tendon ; what was a simple membrane becomes an investing tunic ; what had been cartilage is afterwards found to be a spinous process of bone, all variously diversified out of the same similar mate- rial. For a similar organic body (which the vulgar believe to consist of the elements) is not created out of elements at first existing separately, and then put together, united, and altered ; nor is it put together out of constituent parts; but, from a trans- mutation of it when in a mixed state, another compound is created : to take an instance, from the colliquameut the blood is formed, from the blood the structure of the body arises, which appears to be homogeneous in the beginning, and re- sembles the spermatic jelly ; but from this the parts are at first delineated by an obscure division, and afterwards be- come separate and distinct organs.
Those parts, I say, are not made similar by any successive union of dissimilar and heterogeneous elements, but spring out of a similar material through the process of generation, have their different elements assigned to them by the same process, and are made dissimilar. Just as if the whole chick was cre- ated by a command to this effect, of the Divine Architect : " let there be a similar colourless mass, and let it be divided into parts and made to increase, and in the meantime, while it is growing, let there be a separation and delineation of parts ; and let this part be harder, and denser, and more glistening, that be softer and more coloured," and it was so. Now it is in this very manner that the structure of the chick in the egg goes on day by day ; all its parts are formed, nourished, and augmented out of the same material. First, from the spine
