TWENTIETH CENTURY TEXT-BOOKS OF SCIENCE. 



TEXT-BOOKS OF ZOOLOGY. 



By DAVID STARR JORDAN, Ph. D., LL. D., President of 

 Leland Stanford Junior Univeisity ; VERNON L. KEL- 

 LOGG, M. S., and HAROLD HEATH, Ph. D., Professors 

 in Leland Stanford Junior University. 



Animal Studies. 



An Elementary Zoology. $1.25. 



Animal Life. 



A First Book of Zoology. $1.20. 



Animal Forms. 



A Text-Book of Zoology. $1.10. 



Animals. 



Animal Life and Animal Forms in one volume. $1.80. 



Animal Structures. 



A Laboratory Manual of Zoology. By D. S. JORDAN 

 and GEORGE C. PRICE. 75 cents. 



An Introduction to Physical Geography. 



By GROVE K. GILBERT, LL. D., United States Geolog- 

 ical Survey, and ALBERT P. BRIGHAM, Professor of Geol- 

 ogy, Colgate University. $1.25. 



A Text-Book of Geology. 



By ALBERT PERRY BRIGHAM, A. M. $1.40. 



An Elementary Chemistry. 



With Experiments. By ROBERT HART BRADBURY, 

 A. M., Ph. D., Teacher of Chemistry, Central Manual 

 Training School, Philadelphia. $1.25. Experiments sep- 

 arately, 45 cents. 



The Elementary Principles of Chemistry. 



By ABRAM VAN EPS YOUNG, Ph. B., Northwestern 

 University, Evanston, 111. 95 cents. With Experiments, 

 1. 10. Laboratory Experiments separately, 45 cents. 



D. APPLETON AND COMPANY, NEW YORK. 



