INFORMATION TO SUBSCRIBERS 
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pany, Baltimore, or Arthur L. Day, Home Secretary, National Academy of 
Sciences, Smithsonian Institution, Washington, D. C. Single numbers, $0.50. 
Past publications of the N-ational Academy of Sciences are listed in these 
Proceedings, Volume III, pp. 743-753, December, 1917. In good part these 
publications are no longer available for distribution. Inquiries with regard 
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Single numbers may be obtained for fifty cents except where the sale of such 
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