8 The IntematlonaX Scientific SeTto.— (Contipued.) 



19. ANIMAL PARASITES AND MESSMATES. By ProfesBor P. J. Van Ben- 



EDEN, University of Louvain. With 83 Dlnstrations. Jl .50. 



20. FEEMBNTATION. By Professor P. SoirtTZENBEKGEB. With 28 Illustra- 



tions. $1.50. 



81. THE PIVB SENSES OF MAN. By Professor Julius Beknstein, Univer- 

 sity of Halle. With 91 ninstrations. $1.75. 



83. THE THEOET OP SOUND IN ITS EELATION TO MUSIC. By Pro- 

 fessor PiETBO Blaserha, Eoyal University of Borne. With numerons 

 ~ Illustrations. $1.50. 



23. STUDIES IN SPECTRUM ANALYSIS. By J. Nobman Locktbr, P. E. S. 



With 7 Photographic Ulustratioos of Spectra, and S2 other Illustrations. 

 $2.50. 



24. A HISTOET OP THE GEOWTH OP THE STEAM-ENGINE. By Pro- 



fessor E. H. Thukston, Cornell University. With 163 Blustrations. $2.50. 



25. EDUCATION AS A SCIENCE. By Albxahdek Bain, LL. D. $1.75. 



26. STUDENTS' TEXT-BOOK OP COLOE ; or, Modem Chromatics. With 



Applications to Art and Industry. By Professor Ogden N. Eood, Colum- 

 bia College. With 130 Dlustrations. $2.00. 



27. THE HUMAN SPECIES. By Professor A. de Quatkepages, Museum of 



Natural History, Paris. $2.00. 



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



HuxLET, P. E. S. With 82 Bluetrations. $1.75. 



29. THE ATOMIC THEOET. By Professor A. Wuetz. Translated hy B. 



Cleminshaw, P. C. S. With Illustrative Chart. $1.60. 



80. ANIMAL LIFE AS AFFECTED BY THE NATUEAL CONDITIONS OP 



EXISTENCE. By Professor Kabl Sempbb, University of Wflrzburg. 

 With 106 Illustrations and 2 Maps. $2.00. 



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



By Professor Joseph Le Contb, LL.D., University of California. With 

 132 Dlustrations. $1.50. 

 Si. GENERAL PHYSIOLOGY OP MUSCLES AND NEEVES. By Professor 

 I. Eosenthal, University of Erlangen. With 75 Dlustrations. $1.50. 



33. ILLUSIONS : A Psychological Study. By James Suixt. $1.50. 



34. THE SUN. By Professor C. A. Young, College of New Jersey. With 88 



Dlustrations. $2.00. 



85. VOLCANOES ; What they Are and What they Teach. By Professor John 

 W. JuDD, P. E S., Eoyal School of Mines. With 96 Dlustrations. $2.00. 



36. SUICIDE : An Essay in Comparative Moral Statistics. By Professor Henet 

 Moeselli, M. D., Eoyal University, Turin. With 4 Statistical Maps. 

 $1.75. 



87. THE POEMATION OP VEGETABLE MOULD, THROUGH THE AC- 

 TION OP WOEMS. With Observations on their Habits. By Chableb 

 Dabwin, LL. D., P. E. S. With 15 Dlustrations. $1.50. 



