64 found, did not, he speaks himself as being ' adeo novum et inauditum ut verear ne habeam inimicos omnes homines ; ' and finally, the argument, which though it be indirect, every morphologist will allow to be not only most exquisite, but also most convincing, for the circulation in the adult warm-blooded animal, drawn from the re- lations held by the venae cavae to the ef- ferent arteries in the embryo, and in all animals with but a single or an imperfectly divided ventricle, ' unus duntaxat ventriculus vel quasi unus,' and of which I would recommend every one who is not already acquainted with it, to gain a knowledge from the seventh chapter of the same book, was his, and his alone. With regard to all these points, with regard, that is, to the circulation as a whole ; with regard to the actual demonstration and exhibition of it as apposed to mere guessing about it ; with Regard to all, or nearly all, sound reasoning is to any large portion of it, Harvey, might iave said with Lucretius, 'Avia Pieriduin peragro loca nulliu3 ante Trita solo.'