191-1] Bryant: Economic Status of the Western Mcadoirlark 389 



5. Birds are very important in preserving that balance of 

 nature most suited to the interests of man, and their place can- 

 not be filled by any other class of living things. 



These facts are now familiar. They have furnished a basis 

 for a sane protection, have demonstrated the intricacy of the 

 interactions of organisms, and have helped develop the economic 

 view of birds. 



Although economic ornithology is fundamentally the study 

 of birds from the standpoint of dollars and cents, and, therefore, 

 includes their use as food, as cage birds, etc., yet emphasis has 

 rightly been placed on the study of the food of birds. As a 

 result, economic ornithology is most often iised in a restricted 

 sense and has reference to the study of the food of birds. Great 

 activity is evidenced in this line of work at the present. Not 

 a month passes that there is not some important contribution to 

 economic ornithology, and there is scarcely an entomological re- 

 port that does not mention the value of birds as insect destroyers. 

 To appreciate the work of the present, however, there must needs 

 be some knowledge of the work of the past. A brief historical 

 review of the subject, with emphasis on the methods used, will 

 furnish this needed information. 



HISTORY OF METHODS IN ECONOMIC ORNITHOLOGY 



We need only to examine in detail the progress of our sciences 

 to be convinced that there is such a thing as evolution. As we 

 interpret their progress step by step, and thus survey their gen- 

 eral trend, it would seem that the development has been of the 

 orthogenetic type. The biological sciences have been a little 

 slower than others in their development, but they are now taking 

 front rank. One of the most marked tendencies to be noted in 

 history is that of a change from the period when biologists drew 

 conclusions from facts gained from observation only to the 

 present period when more intensive study and experimental 

 evidence are demanded. 



The period of time previous to 1850 may be termed the prim- 

 itive period, for dui'ing this time we find only an occasional 

 mention of the food habits of birds, the entire time of the workers 



