1906] The Migration of Birds. 39 



Bohemian Waxwing may be present at a place in one winter and 

 then not be seen again there for years. This case is more mys- 

 terious than the others. The same holds good of the Canada Jay, 

 the various redpolls and the Pine Siskin, though in a lesser degree. 

 Then there are the herons, which before starting south in fall 

 from their breeding places, seem to go on a little excursion north- 

 ward first, and are sometimes taken far north of their range. 

 The extraordinary route of the Golden Plover [Chamdriiis donu'iii- 

 cus) and several more shore birds should here be noted. These 

 birds breed in the bleak lands near and beyond the Arctic circle. 

 In August, when the young are able to fly well, they proceed from 

 north-central Canada to Labrador, thence by easy stages to Nova 

 Scotia, etc., from there south over the Atlantic Ocean, to the Ba- 

 hamas, to South America, through Brazil, still south through 

 Argentine to Patagonia, 8,000 miles. After a short stay in that 

 dreary place, they proceed northward again, but by a different 

 route, further west in South America, through Central America, 

 into the wide Mississippi valley, and in that north to their breed- 

 ing place, near the Arctic circle, 16,000 miles in all. 



There are several other birds which go from and back to their 

 breeding range by different routes. Thus I found the rare Cape 

 May Warbler common in fall in western Maryland, but none in 

 the spring. Another curious fact brought to light by the data 

 accumuluting at Washington is the case of the Nashville Warbler. 

 This breeds here and northward and proceeds in fall southward 

 with other warblers, travelling by easy stages, feeding in day time 

 along the way, like any other well-behaved warbler would. But 

 south of the southern boundary of Virginia it is practically un- 

 known, only turning up again in its winter range, Mexico, near 

 Vera Cruz. The only inference left seems to be, that it rises up 

 high into the air at about the latitude of Virginia and flies without 

 alighting again over all the intervening land and the Gulf. Who 

 knows ? The well known and abundant Chimney Swift offers 

 another mystery. It moves southward in fall, its flocks becoming 

 enormously large when they reach the Gulf coast. Then they dis- 

 appear as though the Gulf had swallowed them, until thev turn up 

 again next March bright and cheerful as ever. Where they spent 

 the winter months is a complete mystery so far, and the world is 



