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PRINCIPLES OF 

 STRATIGRAPHY 



BY 



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



PROFESSOR OF PALAEONTOLOGY IN 

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Large Octavo, 1150 pagea, with 264 iUostrBtioni Ib the text. 

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Journal of the Washington 

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ELEVENTH EDITION 



THE MICROSCOPE, 



an Introduction to Microscopic Methods and to Histology, by 

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Laboratory Guide 



for the Study of 



THE FROG 



An Introduction to Anatomy, Histology 

 and Physiology 



By Bertram G. Smith, Ph.D., State Normal College, 

 Ypsilanti, Michigan. 8vo, paper, pp. 77-|-iv. Price, 

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This laboratory guide is the product of eight years' 

 experience in teaching the biology of the frog in the 

 University of Michigan, Syracuse University, the Uni- 

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 The appendix contains directions concerning equipment 

 and the making of permanent preparations. 

 Published by the author 



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