Utility and Eqgnomy of Birds 
value to agriculture of bird-life, of which 
Birds, Insects, and Crops, issuedin March 1917, 
may be noticed as but one example. 
Mention may also be made of the treaty, 
the first instrument of its kind, made be- 
tween the United States and Canada in 1917, 
although its conclusion was due not to the 
War but to the enlightened view of birds 
prevailing across the Atlantic. This treaty 
protected more than a thousand valuable 
species of birds from the Gulf of Mexico to 
the North Pole. It also provided that any 
bird important to agriculture as a destroyer 
of insects should not be killed at any time. 
This, it was reckoned, would save American 
farmers millions of dollars lost through the 
crop depredations of insects (Globe, 12.111.18). 
Dr. Gordon Hewitt, referring to this treaty, 
gave it as his opinion that ‘“‘the protection 
of insectivorous birds is at all times a neces- 
sary measure in crop production. At the 
present time, when the production of food 
crops is not only a national but a world 
necessity, the protection of such birds should 
be regarded as a measure of national defence ”’ 
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