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See also Jour. Hered. 7: 158-164. 



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Science 46: 19-24. 



RITTER, W. E. 1919. The Unity of the Organism. Boston. 



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SCHACKE, M. A. 1919. A chromosome difference between the sexes of Sphcerocarpos 



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SCHAFFNER, J. H. 1919a. Complete reversal of sex in hemp. Science 50: 311-312. 

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2. 



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