ABSTRACT
The refutation of the theory of the unchangeability of the systematic species, which with Lamarck was hardly much more than a simple denial, constitutes the one permanent result of the best known of all theories of evolution termed Darwinism and Lamarckism. ‘The bird, whose needs attract it to the water in order to seek its food therein, spreads its toes apart when it desires to strike the water and swim upon its surface. The skin which unites the toes at their base acquires, by this unceasingly repeated extension of the toes, the habit of spreading itself out. In the plains of La Plata and Patagonia he discovered fossil remains of gigantic Sloths, especially of Dasypus gigas. Of a plan in the evolution of organisms, of a Creator who in some manner established this plan in the organisms, nothing can consequently be said. Each organism is an harmonious whole, in which the most varied parts are combined into a true unit.
