VUl 



PREFACE 



III. The maintenance of life of all sorts by the utiliza- 

 tion of the materials and energy of foods. This involves 

 of course some consideration of the machinery by which 

 metabolism is carried on. 



IV. The mechanisms by which plants and animals 

 adjust their various organs to one another and themselves 

 to their environment both physical and biological, in- 

 volving a consideration of the general structure and func- 

 tion of nervous systems and of hormone secretion. 



V. The interaction of organisms with one another, in- 

 volving such topics as family and herd relationships, 

 human society, symbiosis, parasitism, and disease. 



\T. Death of organisms and of protoplasm. 



\TI. The decomposition of organic remains and the 

 consequent enrichment of the soil, involving a discussion 

 of the biological and chemical processes involved and 

 their relation to the cycles of energy and material. 



VIII. The growth and reproduction of organisms. 



IX. The mechanisms and laws of heredity and their 

 application to the breeding of domesticated plants and 

 animals and to the progress of the human rare. 



X. The facts, the principles, and the results of evolu- 

 tion. 



XI. The facts and principles which are involved in 

 the distribution of organisms in time and space. 



XII. Man's place in nature, involving on the one hand 

 a chscussion of the facts which make man an animal, 

 and on the other hand a setting forth of those even more 

 important facts which lead us to believe that man alone 

 of all animate things is master of the destiny of his race. 



.\ course of this sort necessarily involves a carefully 

 organized laboratory course illustrative of the principles 

 develope<l in the lectures. At Stanford the student may 

 elect to take such a course, maintained for the purpose, or 

 to substitute for it an equivalent amount of elementary 

 botany or zoiilogy. 



Although the authors of this text have borne the chief 



