Note 235 — ON THE WILL IN NATURE. [190] (continued 2)

That the lowest place should be given to the rodents, seems however to proceed from à priori rather than from à posteriori considerations: that is to say, from the circumstance, that their brain has extremely faint or small convolutions; so that too much weight may have been given to this point. In sheep and calves the convolutions are numerous and deep, yet how is it with their intelligence? The mechanical instincts of the beaver are again greatly assisted by its understanding, and even rabbits show remarkable intelligence (see Leroy's beautiful work: "Lettres Philosophiques sur l'Intelligence des Animaux," lettre 3, p. 149). Even rats give proof of quite uncommon intelligence, of which some remarkable instances may be found in the "Quarterly Review," No. 201, Jan.-March, 1857, in a special article entitled "Rats."