brata his views as to the uniformity of animal composition, he found a vigorous opponent in Cuvier. Geoffroy, like Goethe, held that there is in Nature a law of compensation, or balancing of growth, so that if one organ take on an excess of development, it is at the expense of another part; and he maintained that, since Nature takes no sudden leaps, even organs which are superfluous in any given species, if they have played an important part in other species of the same family, are retained as rudiments, which testify to the permanence of the general plan of creation. It was his conviction that, owing to the conditions of life, the same forms had not been perpetuated since the origin of all things, although it was not his belief that existing species were becoming modified. Cuvier, on the other hand, maintained the absolute invariability of species, which, he declared, had been created with regard to the circumstances in which they were placed, each organ con-
