Sterne (Ernest Krause), "Die allgemeine Weltanschauung in ihrer
historischen Entwickelung". Stuttgart, 1889. Chapter entitled
"Bestandigkeit oder Veranderlichkeit der Naturwesen".), went the length of
admitting (in 1762) that new species might arise by intercrossing.
Buffon's position among the pioneers of the evolution-doctrine is weakened
by his habit of vacillating between his own conclusions and the orthodoxy
of the Sorbonne, but there is no doubt that he had a firm grasp of the
general idea of "l'enchainement des etres."

Erasmus Darwin (1731-1802), probably influenced by Buffon, was another firm
evolutionist, and the outline of his argument in the "Zoonomia" ("Zoonomia,
or the Laws of Organic Life", 2 vols. London, 1794; Osborn op. cit. page
145.) might serve in part at least to-day. "When we revolve in our minds
the metamorphoses of animals, as from the tadpole to the frog; secondly,
the changes produced by artificial cultivation, as in the breeds of horses,
dogs, and sheep; thirdly, the changes produced by conditions of climate and
of season, as in the sheep of warm climates being covered with hair instead
of wool, and the hares and partridges of northern climates becoming white
in winter: when, further, we observe the changes of structure produced by
habit, as seen especially in men of different occupations; or the changes
produced by artificial mutilation and prenatal influences, as in the
crossing of species and production of monsters; fourth, when we observe the
essential unity of plan in all warm-blooded animals,--we are led to
conclude that they have been alike produced from a similar living
filament"..."From thus meditating upon the minute portion of time in which
many of the above changes have been produced, would it be too bold to
imagine, in the great length of time since the earth began to exist,
perhaps millions of years before the commencement of the history of
mankind, that all warm-blooded animals have arisen from one living
filament?"..."This idea of the gradual generation of all things seems to