188 FRIENDS WORTH KNOWING. 



The logic of the case is simple; birds will assemble 

 chiefly where food for themselves and their young is in 

 greatest abundance, and where they are least exposed to 

 enemies. These two prime conditions of prosperity, with 

 many favorable concomitants, man's art supplies to the in- 

 sessorial birds, which, on the other hand, suffer little direct 

 injury from his contact. Yet some species seem little af- 

 fected by the civilizing of the country, either in numbers 

 or habits, while others increase rapidly on the first settle- 

 ment of a region, and then decrease again. Of this class 

 are the prairie-hen (Oupidonia cupido) and the mallard. 

 "They find abundance of food in the corn and wheat 

 fields ; while the population is sparse and larger game so 

 abundant, they are hunted very little ; but as the popula- 

 tion increases they are gradually thinned out, and become 

 in some cases exterminated. Other birds, as the quail, are 

 wholly unknown beyond the frontier, and only appear af- 

 ter the country has been settled a short time. Still others, 

 woodland species, appear in regions where they were never 

 known before, as groves of trees are planted, and thick 

 woods spring up on the prairies as soon as the ravages of 

 the fires are checked." 



Striking examples of how some of our birds have accept- 

 ed this tacit invitation to make men their confidants occur 



