1S91.I LooiMis on Birds 0/ Chester Comity, South Carolina. ^\ 



whose centre of abundance lies in the interior. The first inquiry 

 that arises is, how do these birds fj^et here? In seeking an 

 answer to this, an obstacle is encountered at the outset — the com- 

 mon obstacle that confronts every student who endeavors to 

 arrive at conclusions based upon geographical distribution. While 

 it is idle to look for absolute tlata for generalization, yet sufficient 

 is known to remove the subject from the realm of mere conjec- 

 ture. 



The study of the list of trans-Apj)alachian birds occurring in 

 Chester County reveals that they belong to four categories, as 

 follows : — 



I. Those, appearing in winter, which have not been reported 

 on the Atlantic slope, so ftir as known, north of the vSouth Atlan- 

 tic States, — Scolecophagiis cyanoccphalns, Calcnrins pictus^ 

 Avimodrajnus leconteii. 



3. Those, also winter visitants, whose breeding i-ange extends 

 eastward from the Mississippi Valley and the region of the Great 

 Lakes into the North Atlantic States, — Otocoris alpestris prati- 

 cola^ ^uiscaliis quiscula ccnetis. 



3. Those which have been found numerously in Ciiester County 

 during migrations and also, though sparingly, at such times on 

 the Atlantic slope as far north as Washington and New Eng- 

 land, — Dendrolca palmartim^ Sehirus noveboraccvsis notabilis. 



4. Those formerly considered as trans-Appalachian which are 

 now known to breed on both sides of the mountain system, 

 thou<'-h ranging farther north on the western, — Pc/iccca ivstlvalis 

 bachmanii^ Dciidroica doniiiiica albilora. 



There are two movements of 'Western' birds, distinct from 

 each other, demanding exposition. Both are intimately con- 

 nected with the general southward and northward migrations. 

 The first is a movement from northern latitudes in fall and win- 

 ter, the second from southern latitudes in spring. In the order 

 mentioned the movement in a southerly direction is the first pre- 

 senting itself for consideration. To understand fully the signifi- 

 cance of this movement it is necessary to examine in detail the 

 distribution of the birds of categories one and three. From the 

 records it is found that the range of Dendroica palmarum 

 stretches diagonally across the continent from the Great vSlave 

 Lake in the interior of British America to the Bahamas and 

 Greater Antilles. In the central portion of the United States 



