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[31]. l. c., 116. 1896.
[32]. l. c., 3. 1898.
[33]. Uber mechanische Shutzmittel der Samen gegen schädliche Einflüsse von aussen. Engler Bot. Jahrb., 5:56. 1883.
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[37]. When this word was first proposed, the author did not know that Briquet had already applied the term polytopism to this concept (Ann. Conserv. Bot. Gen., 5:73. 1901). Since polygenesis expresses the idea of origin, and applies to multiple origin in time as well as in space, it is retained as the name of this concept. Polytopic and monotopic are adopted for multiple and single origin in space respectively, and polychronic and monochronic are proposed for similar origin in time.