THE 



PRINCIPLES OF BIOLOGY 



BY 



HERBERT ^PENCER 



AUTHOR OF SOCIAL STATfCS, EDUCATION, STUDY OF SOCIOLOGY, 



ESSAYS : SCIENTIFIC, POLITICAL, AND SPECULATIVE, 



FACTORS OF ORGANIC EVOLUTION, ETC. 



IN TWO VOLUMES 

 VOL. I 



NEW YORK 

 D. APPLETON AND COMPANY 



■8,97 



