Finally, it may be noted in passing that, though it is customary with evolutionists to regard homologous characters as the tenaciously persistent heritage of primeval days, and to look upon adaptational characters as adventitious and accessory to the aforesaid primitive heritage, the supposedly older and more fundamental characters fail to give, by the manifestation of greater fixity, any empirical evidence whatever of their being more deeply or firmly rooted in the hereditary process than the presumably newer adaptational characters. We have, therefore, no experimental warrant for appropriating homologous, rather than adaptational, characters to the process of inheritance. “It is sometimes asserted,” says Goodrich, “that old-established characters are inherited, and that newly begotten ones are not, or are less constant, in their reappearance. This statement will not bear critical examination. For, on the one hand, it has been conclusively shown by experimental breeding that the newest characters may be inherited as constantly as the most ancient.... While, on the other hand, few characters in plants can be older than the green color due to chlorophyll, yet it is sufficient to cut off the light from a germinating seed for the greenness to fail to appear. Again, ever since Devonian times vertebrates have inherited paired eyes; yet, as Professor Stockard has shown, if a little magnesium chloride is added to the sea water in which the eggs of the fish _Fundulus_ are developing, they will give rise to embryos with one median cyclopean eye! Nor is the suggestion any happier that the, so to speak, more deep-seated and fundamental characters are more constantly inherited than the trivial or superficial. A glance at the organisms around us, or the slightest experimental trial, soon convinces us that the apparently least important character may reappear as constantly as the most fundamental. But while an organism may live without some trivial character, it can rarely do so when a fundamental character is absent, hence such incomplete individuals are seldom met in Nature.” (_Science_, Dec. 2, 1921, p. 530.) But, whether it be upon, or beneath, the surface, similitude of _any kind_ suffices to establish our contention that inheritance is not the only similifying influence present in organisms, and that resemblance is perfectly compatible with independence of ancestry. We have, therefore, an alternative for inheritance in the explanation of organic uniformities, and by the admission of this alternative, which, for the rest, is factually attested by the universally acknowledged phenomena of convergence, the inference of common descent from structural resemblance is shorn of the last remnant of its demonstrative force, as an _a posteriori_ argument.