CONTENTS 



CHAPTER PAGE 



I. Work of Early Biologists. Explorers and Travel- 

 ers, Collectors, Field Naturalists and Museum 

 Men. Early Surveys, State and National ... 19 



II. Biological Institutions in America. Universities and 

 Colleges, Museums, Botanical and Zoological Gar- 

 dens, Biological Stations and Endowed Labora- 

 tories 47 



III. Descriptive Biology. Development of Plants and 



Animals; of Sex and Sexual Reproduction, and Al- 

 teration OF Generations. The Path of Vertebrate 

 Evolution 88 



IV. The Story of the Rocks. Contribution of Paleon- 



tology TO Evolution. Rise and Fall of the Faunas 



of the Past 116 



V. Geographical Distribution of Plants and Animals. 

 Relation Between Organism and Environment. 

 Methods of, and Barriers to the Spread of Plants 

 and Animals. Plant and Animal Societies. Life 

 Zones op North America 151 



VI. Experimental Biology. Preformation in a New 

 Dress, Organization of the Egg, Regeneration and 

 Grafting, Plastic Surgery, Tissue Culture, the 

 Problem of Death, and Immortality of the Cell . 188 



VII. Experimental Biology Continued. The Role of the 

 Chromosomes in Inheritance. Inheritance of Sex 

 and Sex-Linked Characters 202 



VIII. Experimental Biology Continued. Influence of En- 

 vironment IN Determining the Development of Or- 

 ganisms. Effects of Temperature, Light, Moisture, 

 Chemicals, and Food upon the Form of Animals and 

 Plants. The Control of Sex 219 



IX. Experimental Biology Continued. The Factors of 

 Evolution: Natural Selection, Mutation, Ortho- 

 genesis, Isolation, Inheritance of Acquired Char- 

 acters. Experimental Modification of the Germ 

 Cells 234 



X. Experimental Biology Continued. Mendelism and 

 the Multiple Factor Hypothesis. Human Inherit- 

 ance and Eugenics 257 



XI. Experimental Biology Continued. Mechanism Versus 

 Vitalism. Physico - chemistry op Vital Processes, 

 Metabolism of Animals and Plants 278 



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