The Popular Science Monthly 



EnUred in the Post Office in Lanoaaler, Pa., at aeeend-clcut matter. 



CONTENTS OF MAY NUMBER. 



The Classification of Fishes. President David Starr 

 Jordan. 



Stages oJ Vita) Motion. O. F. Cook. 



The Slavic Immigrant. Ur. Allan McLaughlin. 



Obituary Notice of a Lung-Fish. Professor Bash- 

 ford Dean. 



The Opportunity of the Smaller Museums of Natural 

 History. William Orh. 



College Entrance Examinations. Abraham Flex- 

 nek. 



A New Source of Heat : Radium. Dr. Henry Car- 

 rington Bolton. 



The Decrease in the Size of American Families. Pro- 

 fessor Edward L. Thorndike. 



Helen Keller; A Psychological Autobiography. 

 Professor Joseph Jastrow. 



Discus-^ion and Corrtsjiourtence : ^ 



Prolessor Pearson on the Distribution of Fertility. 

 Edward L. Thorndike. 



Scientific Literature : 



Physiological Chemistry. 



The Progress of Science : 



William Hrirkness; The American Society of 

 Naturalists; Race Senescence; The Field Colum- 

 bian Museum ; The Treatment of Typhoid Kever; 

 The British Antarctic Expedition ; The New 

 York Forest and Game Commission ; Scientific 

 Items. 



CONTENTS OF JULY NUMBER. 



Hertzian Wave Wireless Telegraphy. Professor J. 

 A. Fleming. 



Physiological Economy in Nutrition. Professor R. 

 U. Chittenden. 



Tiie Fie.'d of Municipal Hygiene. Professor Edwin 

 O. Jordan. 



University Tendencies in America. President 

 David Stakr Jordan. 



The Improvement of the City of Washington. 



Changes in the Age of College Graduation. W. Scott 

 Thomas. 



Education Not the Canse of Race Decline. Dr. Geo. 

 J. Engelmann. 



Discussion and Correspondence : 



Magazine Science: B. F. L. 

 Sc;eQti3c Literature : 



Hermann von Helmholtz, 

 The Progress of Science : 



Josiah Willard Gibb:); The Scientific Program of 



the Louisiana Purchase Exposition; Congresses 



of Physicians; Scientific Items. 



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