The International Scientific Series. (Continued.) 



19. ANIMAL PARASITES AND MESSMATES. By Professor P. J. VAN BEN- 

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80. FERMENTATION. By Profes&or P. SCHUTZENBERGEB. With 28 Illustra- 

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21. THE FIVE SENSES OF MAN. By Professor JULIUS BERNSTEIN, Univer- 



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22. THE THEORY OF SOUND IN ITS RELATION TO MUSIC. By Pro- 



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23 STUDIES IN SPECTRUM ANALYSIS. By J. NOBMAN LOCKTEB, F. R. S. 

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24. A HISTORY OF THE GROWTH OF THE STEAM-ENGINE. By Pro- 



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26. -STUDENTS' TEXT-BOOK OF COLOR ; or, Modern Chromatics. With 



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27. THE HUMAN SPECIES. By Professor A. DE QUATREFAGES, Museum of 



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28. THE CRAYFISH : An Introduction to the Study of Zoology. By T. H. 



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29. THE ATOMIC THEORY. By Professor A. WURTZ. Translated by E. 



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30. ANIMAL LIFE AS AFFECTED BY THE NATURAL CONDITIONS OF 



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31. SIGHT : An Exposition of the Principles of Monocular and Binocular Vision. 



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