31 



show how diverse are the appHcations of the process method to inves- 

 tigation. The general idea is easily grasped, but to make the dynamic 

 method a regular habitual procedure in investigation is truly difficult, 

 so difficult, indeed, that there is reasonable ground for doubting if this 

 method can be mastered without a practical application of it to a con- 

 crete problem, at the same time giving special attention to the method 

 of procedure. 



REFERENCES TO LITERATURE 



Adams, C. C. 



'04. On the analogy between the departure from optimum vital 

 conditions and departure from geographical life centers. 

 Science, n. s., 19:210-211. 

 '13. Guide to the study of animal ecology. 183 pp. New York. 

 (This book contains numerous references to the literature bearing upon the 

 subject of this article.) 



Bancroft, W. D. 



'11. A universal law. Science, n. s., 23: 159-179. 



Blackman, F. F. 



'05. Optima and limiting factors. Ann. Bot. 19:281-295. 



Blackman, F. F. and Smith, A. M. 



'11. Experimental researches on vegetable assimilation and res- 

 piration. IX. On assimilation in submerged water-plants, 

 and its relation to the concentration of carbon dioxide and 

 other factors. Proc. Royal Society, B., 83: 389-412, 1910. 



Brooks, W. K. 



'99. The foundations of zoology. 339 pp. New York. 



Cowles, H. C. 



'11. The causes of vegetative cycles. Bot. Gaz., 51:161-183; 

 also, Ann. Assoc. Amer. Geogr., i : 1-20. 19 12. 



