It would be absurd to apportion the intellect of animals to the place which they occupy in zoological classification. We do not possess any certain method by which to form such an appreciation in detail. We remain within the terms of a very acceptable philosophical thesis in advancing our belief, in a general manner, that the intellectual faculties of animals augment from the mollusk to the mammifer, following almost exactly the progressive scale of zoological classification, but to enter into the peculiarities of these orders would be to expose ourselves to certain contradiction. In zoophytes the soul exists as a germ; this germ develops itself and grows in mollusca, and then in articulated creatures and fishes. The soul acquires certain faculties, more or less obscure and dim, when it enters the body of a reptile, and these faculties are manifestly augmented in the body of a bird. The soul is provided with far more perfected faculties when it reaches the body of a mammifer. Such is the general outline of our system. Let us now follow this system out to the end. In the first pages of this book, we have advanced our theory that the soul of man, at the close of its terrestrial existence, passes into the planetary ether, where it is lodged in the body of a new being, superior to man in intelligence and morality. If this theory be correct, if this migration of the soul of man into the body of the superhuman being be real, analogy obliges us to establish the same relation between the animals, and then between the animals and man. We firmly believe that a transmigration, a transmission of souls, or of the germs of souls, throughout the entire series of the classes of animals takes place. The germ of a conscious soul which existed in the zoophyte and the mollusk passes, on the death of those beings, into the body of an articulated animal. In this first stage of its journey, the animate germ strengthens and ameliorates itself. The nascent soul acquires some rudimentary faculties. When this rudiment of a conscious soul passes out of the body of an articulated animal into that of a fish or a reptile, it undergoes a new degree of elaboration, and its power increases. When, escaping from the body of the reptile or the fish, it is lodged in the form of the bird it receives other impressions, which become the origin of new perfections. The bird transmits the spiritual element, already much modified and aggrandized, to the mammifer, and then, the soul, having again gained power, and the number of its faculties being augmented, passes into the body of man. It is probable that in the case of the inferior animals many animate germs are united to form the superior being. For instance, the principal animators of a certain number of little zoophytes, of those beings who live in the waters by millions, may, probably, on quitting the bodies of those beings, be united in one in order to form the soul of a single individual of a superior order.