AIM, CONTENT, AND POINT OF VIEW 15 



and genetic. The developmental or explanatory 

 method is so difficult that every possible expedient 

 observation, comparison, reflection, experiment, etc. 

 must be used to secure the proper development 

 of the main phases of ecology. There is a marked 

 tendency in the naturalist to master one system of 

 work, as observation or experiment, and to use it as 

 a tool almost exclusively, turning from one phase 

 of the subject to another, and continuing the use 

 of the same method. This way of working is favor- 

 able to a good technique, but its weakness is that it 

 often tends to give its user a feeling of the great 

 superiority and reliability of the result reached by 

 his method, and a correspondingly less appreciative 

 recognition of results secured by other methods. 

 To observe, to experiment, to reflect, to dissect, 

 to stain, and to collect are only partial methods of 

 investigation, and this fact should be realized and 

 be kept in mind when estimating values and planning 

 work. 



The aim of the ecologist is professedly genetic 

 or explanatory because it is the study of responses to 

 all conditions of the complete environment. But 

 these responses must be described, and the conditions 

 influencing them as well, so that a descriptive aspect 

 is an essential part in all phases of ecology. In the 

 study of the responses of an individual, an order, 

 or an association, pure description of the responses is 

 necessary; but a description which will at once 

 describe and show the working of the processes by 

 which the results were produced, is of quite a different 



