II. 



"I cannot too strongly emphasize the fact . . . that a com- 

 prehensive survey of our entire natural history is absolutely es- 

 sential to a good working knowledge of those parts of it which 

 chiefly attract popular attention, that is, its edible fishes, its 

 injurious and beneficial insects, and its parasitic plants. Such a 

 survey, however, should not stop with a study of the dead forms 

 of nature, ending in mere lists and descriptions. To have an 

 applicable value, it must treat the life of the region as an organic 

 unit, must study it in action, and direct principal attention to 

 the laws of its activity." S. A. FORBES. 1883. 



NATURAL history surveys have come down to us 

 from the early days of zoology. These surveys have 

 been of many kinds and have ranged from the 

 adventurous accounts of early and daring explorers 

 to those of such naturalists as Belt, Bates, Wallace, 

 and Darwin, onward to the voluminous accounts of 

 the "Biologia Centrali-Americana," and in the Chal- 

 lenger reports. These surveys have contributed 

 greatly to our knowledge of the fundamental facts 

 of zoology and to the training of naturalists. 



The most frequent form of survey is that carried 

 on along the lines which most nearly approach 

 individual and aggregate ecology. Most of such 

 surveys give only slight attention to the responsive 

 relation, or only to its most general aspects. Surveys 



23 



