"on the formation of the fœtus, where numerous problems of the following order can find a place: Why should this part be made or perfected earlier, that later? As regards the dominance of the members: Which part is the cause of the other? There are very many problems connected with the heart, such as: Why should it be the first thing (as Aristotle says in his third book On the Parts of Animals)[127] to acquire consistency, and be seen possessed of life, motion, and sensation, before anything has been perfected in the rest of the body? And in like manner regarding the blood: Why is it before all, and how possessed of the beginnings[128] of life and of the animal, and of the craving to move and be impelled hither and thither, to which end the heart would seem to have been made?"[129] That Harvey should have printed this passage in 1628, in the same work with his repeated eulogies of the Aristotelian heart, shows that the idea of the possible primacy of the blood must have been in his mind early. It was, indeed, so from the jotting down of his private notes of 1616, to the publication of the Exercises to Riolanus in 1649 and the treatise On Generation in 1651. The same mental attitude is revealed, perhaps more strongly, in the following passage of an earlier chapter of Harvey's treatise of 1628. Here we come upon the thought that it may be the blood, and neither ventricle nor auricle, which is the last to die. Harvey says:-- "Besides this, however, I have occasionally observed, after the heart and even its right auricle[197] had ceased their pulsations as though in the act of dying, that an obscure motion and flow and a sort of palpitation manifestly remained in the blood itself contained in the right auricle, so long, that is, as the blood appeared to be imbued with heat and spirits. Something of the sort is very plainly to be seen at the beginning of the generation of an animal, in the hen's egg within the first seven days of incubation. There is present, first and before all else, a drop of blood which palpitates (as Aristotle also noted); from which, when growth has taken place and the chick has been formed to some extent, the auricles of the heart are made; and in these, which pulsate perpetually, life inheres.... "Whoever, therefore, shall choose to investigate more closely will say that the heart is not the first to live and the last to die, but that the auricles, and the part which answers thereto in serpents, fishes, and such animals, are alive sooner than the heart itself and also die later than the heart. Whether even earlier the blood itself, or the spirit, have not an obscure palpitation of its own, which it has seemed to me to retain after death, may well be questioned; and whether we should not speak of life as beginning with palpitation."[198]