"iSol I Loomis on Birds of Chester County, South Carolina. 7K 



irregularly, being present for one or more seasons and then rare 

 or absent for a varying period. 1 The Dickcissel is a remarkable 

 example. During the first half dozen years I paid attention to 

 the birds of this section it was not observed, then it was common 

 locally for two summers. Afterwards it was not met with 

 though my observations were continued six years longer. 2 A 

 parallel on a smaller scale, immediately under the eye, appears 

 to be supplied in the shifting of breeding grounds, as observed 

 here in the Meadowlark — a particular field being in favor for a 

 single season or longer and then deserted and another, perhaps a 

 mile or two away, occupied. In lapse of time there may be a 

 returning to former haunts. The Meadowlark is also more 

 numerous in some summers than others. This fluctuation in 

 abundance is esteemed to be but a more extended shifting of 

 breeding grounds — the position of isolated communities varying 

 so that different localities are occupied in different seasons. As 

 the increase is abrupt instead of gradual it is obvious that the 

 fluctuations do not arise from destruction of the birds. It has 

 not been determined that storms in anyway influence the location 

 of isolated communities. 



The irregularity here in winter of the Robin, Bewick's Wren, 

 and cei"tain other birds has been commented upon at length in a 

 former part of this article, and explained also on the ground of 

 variability in location of isolated communities. A parallel in 

 miniature seems to be found in the restricted distribution 

 of some of the less abundant winter birds of this neigh- 

 borhood, particular situations being frequented for the season to 

 the exclusion of others apparently equally attractive. That 

 migration does not fail to take place in the Robin or Bewick's 

 Wren when either is wanting in winter is proven by their occur- 

 rence during the height of migration. The presence of the 



1 I speak with some positiveness of the absence of birds, as I have had opportunity 

 for thorough observation, not having been trammelled by the restrictions prevailing in 

 more thickly settled communities. 



2 Instances of its erratic appearance or abandonment are not wanting in other local- 

 ities. Cf. Langdon (Ohio), Abst. Proc. Linn. Soc. N. Y., No. 5, p. 11 ; Butler, 'Birds 

 of Indiana,' p. 77 ; Coues and Prentiss, 'Avifauna Columbiana,' p. 67 ; Merriam (Con- 

 necticut), Trans. Conn. Acad., IV, p. 43; Trotter (vicinity of Philadelphia), B. N. 

 O. C, IV, p. 235; Lloyd (western Texas), Auk, IV, p. 294; Dutcher (Long Island), 

 ibid., VI, p. 137 ; etc. 



