^CIENCB-'ADVERTISEMENTS 



P RINCIPLES OF 

 STRATIGRAPHY 



BY 

 AMADEUS W. GRABAU. S.M.. S.D. 



PROFESSOR OF PALEONTOLOGY IN 

 COLUMBIA UNIVERSITY 



"Should be on the reference shelf of every col- 

 lege, normal school, and large high school in the 

 United States." — Journal of Geography. Vol. XII I, 

 Jan. 1915. 



avm. 1 ISO page; 284 iltuMtrationt. Price, fT. SO 



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a shredded form of the purest concentrated 

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Many laboratory workers are using Parlodion 

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Parlodion is non-explosive, keeps indefinitely 

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Parlodion may be obtained from your whole- 

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Du Pont ChenriicaS Works 



Dept. 6i£ Equitabae Bidg., New York City 



The IVIiorosoope 



12th E<Iition, Published April 10, 1917 



Re-Written and larsely Re-Illiutrated 



Br SIMON HENRY CAGE of Cornell Univereltr 



Postpaid $3.00 



COMSTOCK PUBLISHING CO., Ithaca, N. Y. 



Memoirs »f the Wistar Institute of Anatomy and 

 Kology. No. 6, 1915 



THE RAT 



Data and Reference Tables. 278 Pages. 89 Tables. 



Biblioraphy. 

 Compiled and Edited by HENRY H. DONALDSON. 



Postpaid S3.00. 



Philadelphia, Pa. 



The Wistar Institute 



WANTED 



Journal of Physiology, British, Vols. 1-47 

 Centralblatt fiir Physiologie, complete set 



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Western University Medical School 



LONDON, CANADA 



The Ellen Richards Research Prize 



The Naples Table Association for Promoting 

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 823 Wayland Avenue, Providence, R. I. 



NATURAL HISTORY OF MAN 



18,000 Specimens illustrating the daily life of 

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1. Zoology-. Preserved material of all types of animals 

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