370 Distribution of Land Birds. [ ZOE 
on March 20, 1880; another was taken at Riverside, San Bernardino 
County, on February 10, 1888, and a third on December 1, 1888, by 
Mr. W. W. Price; while Mr. Jeffries, in the Auk, records as a fourth 
capture a specimen taken at Santa Barbara on April 1, 1889. Mr. 
F. H. Holmes has told me of still another specimen which he took, 
but I do not know the locality or date. Nearly all of these speci- 
mens have been identified by Mr. Ridgway as typical Yunco hye- 
malis.- Of the fox sparrow ( Passerella iliaca), only one typical 
specimen has been recorded from California’, it having been taken 
by Mr. A. M. Ingersoll, at Poway, San Diego County, January 3, 
1888,* but in the appendix to the History of North American Land 
Birds (iii, p. 516), ‘‘the capture of a specimen exactly intermediate 
between P. z/zaca and P. townsendzi, at Saticoy, California, Decem- 
ber, 14, 1872, by Dr. J. G. Cooper,” is recorded. Mr. L. Belding 
has recorded the capture ofa typical specimen of the downy wood- 
pecker ( Dryobates pubescens ) at Marysville on December 27, 1877,+ 
the only one ever taken within our limits. 
It will be noticed that all of the above records were made at times 
when the western variety of the species was common in the same 
locality, and none were taken during the breeding season. At first 
sight it might seem possible to explain the presence of these birds 
by reversion. Our western varieties, being only nascent species, 
might be supposed to have occasionally reverted to an earlier type; 
but the great objection to this theory is that these western captures 
being typical eastern forms of to-day, we would be compelled to 
assume that the eastern species had remained at a standstill during 
the time which had elapsed since the western forms had commenced 
to evolve. This, although possible in exceptional cases, seems 
highly improbable. To the theory that certain individuals had es- 
caped the influences which had operated in producing the variety 
the same objection would hold good. Still, California has doubt- 
less seen more changes of climate and physical features during re- 
cent geological time than the Eastern States, which might have 
produced a more rapid change in western forms than in eastern. 
The above theories might serve to account for Dryobates pubes- 
cens, but with Yunco hyemalis and Passerella tliaca an easier expla- 
* Proc. Cal. Acad. Sci., ii, 2d Ser., p. go. 
t Proc, U. S, Nat. Mus., 1878, p. 428. 
