xxiv Contents 



CHAPTER PAGE 



in hydroids, 68. Remarks on the relation of germ-cells to 

 germ-layers and to the organism generally, 72. The relation of 

 ideas and^observations as exemplified in the discussions of this 

 chapter, 74. 



IV. THE ORGANISM AND ITS CHEMISTRY 75 



Standpoint of the discussion that of the evolutionary natural- 

 ist, 75. The organism, as a chemical laboratory, 78. Different 

 organisms as different chemical laboratories, 83. (a.) Different 

 odors and flavors of animals and plants as distinguishable by 

 man, 84. (6) Differences in animal odors as distinguished by 

 animals themselves, 88. The naturalist's approach to biochem- 

 ical problems, 90. Some biochemical results viewed from, the 

 naturalist's standpoint, 95. (a) Reichert and Brown's results 



on haemoglobin, 95; (6) The precipitin reaction between bloods 

 of different animals, 99; (c) Comparative chemistry of the 

 sperm of different species of fishes, 102; (d) Comparative 

 chemistry of milk of different species, 103; (e) Comparative 

 chemistry of digestive enzymes, 104; (f) Instances in general 

 biochemistry where interesting facts of comparative chemistry 

 are incidentally brought out, 106. The coalescence of natural 

 history and comparative biochemistry, 107. Provisional enu- 

 meration of chemico-naturalist inquiries, 109. Peculiar im- 

 portance to natural history of the application of physical 

 chemistry to the chemistry of living beings, 110: (a) Indi- 

 viduation and speciation of "organic matter" fundamental 

 biologic facts, 111; (6) Indications that variation and indi- 

 viduation are primarily chemical, while constancy and uni- 

 formity are primarily physical, 115. 



V. THE ORGANISM AND ITS PROTOPLASM 120 



Protoplasm and mystification, 120. Responsibility for the 

 mystification of protoplasm, 121. Conception of animal sar- 

 code and plant protoplasm as "identical stuffs," 123. Max 

 Schultze's actual teachings as to protoplasm and sarcode, 125: 

 (a) Cell nucleus distinct from protoplasm, but both nucleus 

 and protoplasm essential to life of cell, 126; (6) Recognized 

 common attributes but not identity of protoplasm in all or- 

 ganisms, 128. Ernst Brucke's conception of the cell as an 

 organism, 129. Characteristic organization in all cells, 131. 

 Results of later description and classification of cell sub- 



