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Webster, F. M. 



1889. Southern Spread of the Colorado Potato Beetle. U. S. Dept. Agri., Insect Life, 

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Wallace, a. r. 



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Walsh, B. D. 



1S65. The New Potato-bug and Its Natural History. Pract. Ent., vol. I, No. 1. 

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Weismann, A. 



1882. Studies in the Theory of Descent. 2 vols., 729 pp. 



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Yule, G. U. 



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