jgL I Loomis on Birds of Chester County, South Carolina. "1 "2 



sippi Valley is frequently alluded to in the 'Report on Bird 

 Migration.' In this locality this is seen in miniature, the first 

 arrivals from the south in many species usually being found along 

 the streams leading to the Broad and Catawba Rivers and the 

 Low-Country. On the coast, in the northward movement, birds, 

 as a rule, appear sooner than in the Piedmont Region. For 

 example, Dr. Cones mentions the occurrence of the Tree 

 Swallow in numbers at Fort Macon, N. C, in January (Proc. 

 Acad. Nat. Sci. Phila., 1S71, p. 21). In this locality none 

 have ever been seen hefo re March. The loitering of species along 

 the coast in autumn lengthens out their period of migration, the 

 closing movements taking place later than in the Piedmont 

 Region. 



II. Variability hi the Occurrence of Breeding and Winter 



Residents Independent of Failure of Food or 



Severity or Mildness of Season. 



Isolated Communities. — The spirit of gregariousness is a 

 marked feature in bird life. It is manifested after the breeding- 

 season in the woodland groups of associated Titmice, Chickadees, 

 Kinglets, etc., in the winter assemblages of Vesper Sparrows, 

 American Crows, Meadowlarks, or Robins, and in the congrega- 

 tion of the highly gregarious species, as the 'Blackbirds' and the 

 Passenger Pigeon, and in a lower degree in the breeding colonies 

 where the birds are generally dispersed within circumscribed 

 limits, as in the Grasshopper Sparrow, and perhaps as in the 

 Scarlet Tanager as observed by myself at Caesar's Head (Auk, 

 VIII, p. 329) and other birds similarly restricted. As the spirit 

 to concentrate is so dominant, *and as there is local distribution 

 even within the narrow bounds of a neighborhood, it is not 

 strange that there should be local distribution involving larger 

 areas, particularly where a species is not sufficiently abundant to 

 fully occupy a territory, either through actual paucity, or because 

 the territory is on the borders of the habitat. So it happens that 

 toward the extremes of range the individuals of a species, in many 

 birds at least, are inclined to aggregate into isolated communi- 

 ties, being more or less plentiful in a particular locality while the 



