21 



and apparently pass slowly southward. By the middle of August 

 most of the Swallows, Kingbirds and Orioles have disappeared from 

 the interior, and begin to congregate along the river valleys, coast 

 lines and other avenues of migration, whence they pass southward 

 gradually as they are joined by tlocks from farther north. 



Immense congregations of Kingbirds and several species of Swal- 

 lows are familiar sights at this time along the New Jersey coast. 



Grackles, Red-winged Blackbirds, Robins and Bluebirds collect in 

 flocks by August 1, or earlier, but they do not apparently journey 

 southward till later in the season. The pioneer migrants from the 

 north reach Philadelphia during the first week of August, the Water- 

 Thrush and Redstart being the earliest to arrive. During tlie latter 

 part of the month — August 20-31 — many other species arrive, such 

 as the Canadian, Black-throated Blue, Chestnut-sided, Bay-breasted, 

 Blackburnian, Magnolia, and Wilson's Warblers, and the Wilson's 

 Thrush. None of these birds, however, are abundant at this time, 

 and seem to pass through quickly. The majority of these August 

 Warblers that have been collected seem to be old birds, while the 

 large majority of those which pass through later are, as is generally 

 known, birds of the year. 



The bulk of the Warblers, Vireos, Tanagers and the Thrushes, 

 which characterize the May migration in spring, pass through in the 

 fall from September 10 to October 1, and by the end of the first 

 week of the latter month nearly all the stragglers have disappeared. 



The October birds correspond in general to those of the April 

 migration, occurring, of course, in inverse order, and by November 

 1 only a few Hermit Thrushes, Fox Sparrows, Field Sparrows 

 and Myrtle Warblers are left of the migrating birds, while all the 

 winter visitants have arrived in force. 



The Snowbirds begin to arrive as early as September 27, though 

 they are not common before the middle of October. The first 

 White-throated Sparrows are seen about September 20, while on the 

 coast the Herring Gulls arrive at Atlantic City about October 1. 



Such is a brief outline of the spring and fall migrations in the 

 vicinity of Philadelphia. 



Study of Migration in the Delaware Valley — Methods and Results. 

 — The general subject of bird migration having always been a matter 

 of deep interest to the Delaware Valley Ornithological Club and of 

 great importance in the study of ornithology, we feel justified in 

 adding a few extracts from the records of the Club, which serve to 



