THE GRAY SQUIRREL 



TEADILY the forests have been felled, 

 and with them the gray squirrels have 

 gradually disappeared, until their num- 

 bers have so decreased that for a hundred and fifty 

 years there has not occurred one of those great 

 squirrel migrations so common in the United States 

 during the time of the early settlers. Guided by 

 an impulse still unfathomed by naturalists, the 

 squirrels congregated in vast armies and marched 

 across the country. The distance over which they 

 moved was largely governed by the obstacles which 

 they encountered — rivers, lakes, and mountains. The 

 climatic conditions and the food supply by the way, 

 according as they were favorable or unfavorable, 

 lengthened or shortened these migrations. As the 

 squirrels pushed blindly forward, thousands upon 

 thousands perished by the way, and the survivors 

 gradually spread over a great territory, until lost in 

 the vast wilderness. 



Years might elapse before another great migration 



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