Popular Science Monthly/Volume 55/September 1899/Sketch of ...
With his removal to Strasburg, what both Erich Schmidt and Professor von Graff call the third period of Schmidt's scientific career began. It was a period of undisturbed ease in his home life, and was devoted chiefly to the continuation of the studies of the sponges, with a few special researches, the results of which appeared in books, on the theory of descent, fossil animals, on Hartman's theories, and on social democracy. His systematic and anatomical labors on the sponges—the provisional...
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