| Essex Field Club - 1883 - 944 lehte
...which has regulated the Introduction of new Species," Mr. Wallace shows by various lines of argument that " every species has come into existence coincident...space with a pre-existing closely allied species." In 1858 Mr. Wallace sent from Ternate another paper, " On the tendency of Varieties to depart indefinitely... | |
| Robert Greenleaf Leavitt - 1907 - 42 lehte
...published an essay arguing for the evolutionary conception of organic history, the main thesis being this: "Every species has come into existence coincident...space with a pre-existing closely allied species." Thus the evolutionist has been under deep obligation to the taxonomer from the beginning. The obligation... | |
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