PROBLEMS OF MODERN SCIENCE 



later, and in the founding of the Journal oj Ecology 

 in 1913. In the meantime ecology has tended to 

 become a more exact science, using instruments 

 for the determination of soil evaporation, trans- 

 piration of the plant, diurnal variations in sunlight, 

 moisture in the air, rainfall, temperature, and 

 various other factors that affect the plant in rela- 

 tion to its environment. Indeed, ecology in these 

 aspects is now recognised as an essential branch 

 of plant-physiology, for obviously a study of the 

 reactions of the plant in its natural environment 

 in association with its fellows will throw light upon 

 many questions which could not be answered by 

 laboratory experiments. This method of making 

 the plant answer questions where it lives and grows 

 is a most promising field for future research, bear- 

 ing as it does on questions of ecology, physiology, 

 variation, and evolution. 



MICROSCOPIC RESEARCH 



The microscope is, of course, one of the biolo- 

 gist's most valuable instruments of research, and 

 in recent years it has been put to new uses. Valu- 

 able and essential as are the ordinary methods of 

 fixing and staining for the investigation of struc- 

 ture, there are many other facts about protoplasmic 

 structure which can only be determined in the living 

 cell. Methods of micro-dissection of living cells 

 under the highest powers of the microscope by 

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