ESTIMATING THE STOMACH CONTENTS OF WILD BIRDS 107 



McAtee sums up the matter very tersely as follows : " We 

 must express ourselves in terms of bulk also when we desire 

 to state the amount of damage done to crops. The cultivator 

 wishes to know how many quarts of cherries or pecks 

 of grain the birds are apt to destroy in a year. . . . Suppose, 

 using the numerical system, we say we have examined 100 

 Crow stomachs and found in them 675 kernels of corn. 

 What does this mean? Can we learn by numerical 



NEUTRAL 

 70-4- 



IKIJ 



URIES. J 



BENEFITS. 

 2GZ 



Fig. II. 

 Diagram summarising Injuries, Benefits, etc., of Pheasant. 



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comparison with the grasshoppers or acorns eaten, what 

 proportion of the yearly food consists of corn ? The case is 

 different if we can say corn constituted 15 per cent, of the 

 food of these Crows. We then know something about the 

 Crows' relative taste for corn, know that they could have 

 taken much more, but chose to eat other things. The 

 farmer in the locality in which they were collected knows 

 from such a statement about what damage he may expect 

 from Crows." 



It is sincerely to be hoped that in all future investiga- 



