228 MAMMALIA. 



that the misunderstanding is wholly in regard to the possession of the 

 nuts. The red-headed is the only species of woodpecker that I 

 have seen quarrel with the Gray Squirrel. 



On the /th of November, 1879, I witnessed an excitino- skirmish 



o 



between a goshawk and a Gray Squirrel. The hawk dove repeatedly 

 for the Squirrel, and as often did the latter evade him by quickly 

 sliding around the trunk. I le then chippered and scolded and shook 

 his tail in the most aggravating manncM" imaginable. The hawk was 

 much enraged, but finding hims(;lf unable to capture the object of 

 his pursuit, fmall)- alighted to wait till the Squirrel should venture 

 on a limb — a proceeding which the latter wisely showed no inclina- 

 tion to attempt. I put an end to the affair b)' shooting the hawk. 

 Audubon and Bachman state that the red-tailed hawks hunt them in 

 pairs, thus rendering the capture of the helpless aniriial certain and 

 easy. 



The minor migratory movements of this species occur with more 

 or less regularity from \-ear to year, but on so small a scale as to 

 escape general notice. They must not be confounded with the great 

 migrations, not rare in former times, when these animals, actuated by 

 some unknown influence, congregated in vast armies and moved over 

 the land, crossing open prairies, climbing rugged mountains, and 

 swiniming lakas and rivers that lay in their path. Though hundreds. 

 and sometimes thousands, perished b}- the way, the. multitude nioved 

 on, devouring the nuts that grew in the forests through which they 

 passed, and devastating the grain fields of the farmer along the route. 

 Though these remarkable expeditions have been known and com- 

 mented upon for many years, yet our knowledge of them is limited 

 almost to the recognition of the feet of their existence. Scarcity of 

 food very probably gives rise to the disquieting impulse that prompts 

 them to leave their homes, but the true motives that operate in 

 drawing them together, and in determining the direction and distance 

 of their journeys, are as little understood to-day as they were before 

 the discovery of the continent on which they dwell. 



