February 



investigation after an unusually vernal day (and 

 especially after one or two warm and cloudy 

 nights), one is likely to find fresh accessions to 

 such species as had already appeared, as well 

 as forerunners of new species. Thus, while it 

 may be true that none of the individuals re- 

 main more than a few days in a place, replen- 

 ishment will keep a species represented in a 

 given locality for many weeks, which is most 

 fortunate for the student. 



The fall migrations are less favorable for ob- 

 servations, not only for reasons already given, 

 but for others to be cited hereafter, so that we 

 must rely chiefly upon our opportunities in 

 April and May for learning what we can of the 

 "migrants." Without special attention given 

 to the subject during this period, one will never 

 make the acquaintance of some of the most 

 beautiful and rare specimens, and some of the 

 finest singers as well. 



The migratory movement of birds begins, for 

 this latitude, sometimes as early as the middle 

 of February, when the song sparrows begin to 

 appear, and the snow-birds considerably increase 

 in number, and continues until a little into June. 

 One of the last migrants to disappear is the 

 olive-backed thrush, which I saw June 2d ; and 



55 



