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Book Title
über den Einfluss der Isolirung auf die Artbildung
Publication Details
Leipzig, W. Engelmann, 1872
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Cambridge University Library
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Darwin Estate and Cambridge University Library

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annotation Weismann Einfluss der Isolirung.
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annotation p. 8 «p 12 p. 41» on th Hilgendorf case of Planorbis — periods of Variability succeeded by Constancy — (Mem. Forbes case in Purbeck Beds) «p. 137» good argumnts M. Wagner

annotation p. ‹20› 42— on manner in which these forms of Planorbis become constant.
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annotation p. 45 In a «variable» colonist to remain constant mny individuals must immigrate

annotation 47.    Abut drying of eggs of Apus & revival.
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annotation 48 Isolation by itself does nothing

annotation 51. Periods of variability long, yet shorter than those of constancy .

annotation 52.    My argument: M.S. against periods of variability.

annotation ― «p 54» Lays greatest stress on difference in results when a variable or constant species is a Colonist

annotation p. 55 Protective resemblance of Butterflies
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annotation p 65    case of constant Butterflies in separated arenas during Glacial period.—

annotation p. 67    He calls it amixie th non-crssing & acconts for vy local forms by th same «p. 74» proportion of variation not occurng in area stocked by vry few individuals — I shd think slightly differnt conditions wd likewise influence th propagation of variation.— The difference thus gained wd. never exceed th amnt of «individual» differences in species in question
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annotation p. 76    cases of extremely slight difference in differt countries of Lepidoptera — ‹many› «most» species do not present any local vars.
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annotation p 85 Effects of crossng slight & slow except in locomotive organisms.

annotation 95 97 102 } Does he not ignore effects of conditions long-continued.— p 102 good argumnt against.

annotation 107. local form of Butterflies has never spred from Corsica to mainland of Italy.

annotation 106. Cause of richness of endemic forms on islands in part due to such when once formed not spreading to other areas.