72 THE MIGRATION OF BIRDS. 



or little parties of birds, may be seen from time 

 to time during the day flitting along ; or suddenly 

 a district may swarm with a species or even a 

 number of species, which remain loafing about for 

 the day, but not one will be left by the morrow. 



The punctuality of arrival of birds either at their 

 summer or winter quarters, or at various points en 

 route, is nothing less than astonishing. Taking 

 into account the length of the journey they have 

 come, and the consequent number and variety of 

 possible causes of delay, the best kept time of the 

 crack expresses, or the passages of the fastest 

 steamers that plough the ocean with a space-annihi- 

 lating speed, absolutely suffers by comparison! 

 A one hour late in the 200 miles' run of an express, 

 or twenty-four in the 5000 miles' voyage of a 

 steamer, is certainly, all things considered, a far 

 worse record than the one day late in the 5000 

 miles, or the couple of days in 10,000 miles' flight 

 of a bird, at the mercy of countless contingencies 

 neither the train nor the boat have to battle with. 

 And yet this is the simple statement of facts. 

 Migratory birds may be looked for almost to the 

 day, as any one can prove by keeping a record 

 during a series of years. The arrival of sea birds 

 at many of their breeding-places is so regular, that 

 it forms a date in the calendar of men most con- 

 cerned in the event. Of course, the date of arrival 

 varies a good deal with different species. Some 

 species migrate earlier, some later than others; the 

 migration flight of each being regulated by various 



