VOL. I.] Distribution of Land Birds. 371 
nation can, I think, be found. Both birds breed in Alaska, and it 
is highly probable that individuals occasionally wander from their 
southeastern course, thus reaching California. The frequency of 
the occurrence of Yunco hyemalis would seem to indicate this, as 
well as the occurrence of a sparrow exactly intermediate between 
Passerella tliaca and P. iliaca townsendii. The habitats of the two 
birds in Alaska are adjoining, and this intermediate specimen may 
be either a hybrid or, more probably, a form from the locality where 
the two varieties intergrade. 
There are two other eastern species which have no western rep- 
resentatives, but whose occurrence within our limits may easily be 
accounted for in the same way as the preceding, viz: by straying 
from their regular southeastern route of migration and coming south 
with our regular fall migrants. These two are the cat bird ( Galeos- 
coptes carolinensis), and the redstart (Setophaga ruticilla), both of 
which Mr. Clark P. Streator has found breeding commonly in British 
Columbia.* There are, however,a number of eastern species which 
cannot be so easily accounted for. Such are the white-throated 
sparrow (Zonotrichia albicollis), the black and white warbler 
( Mniotilta varia) and the ceerulean warbler ( Dendroica cerulescens an 
None of these species ever normally reach any part of the Pacific 
Coast, so far as we now know, and yet two instances are on record 
of the capture of the first mentioned species in the vicinity of San 
Francisco Bay.t Mr. W. Otto Emerson took one at Haywards on 
November 20, 1889, and Mr. T. E. Slevin collected one near San 
Francisco on December 23, 1888. The two warblers were taken by 
Mr. Emerson on the Farallon Islands, and their records so far re- 
main unique. These islands appear to lie in the direct path of mi- 
grating birds and to afford a convenient resting-place for the weary 
wanderers. 
We do not find the same difficulty in accounting for the two 
specimens of Grinnell’s water thrush (Se‘urus noveboracensis nota- 
bilis), which Mr. A. M. Ingersoll has collected—one at Santa Cruz 
on September 21, 1885, and the other at San Diego on September 
11, 1887. The only wonder is that the bird is not more common 
within our limits, as it is found both north and south of California. 
* Bull, Am. Mus. Nat. Hist., Vol. iii, No. 1, pp. 151-152. 
t Zoe, i, 2, pp. 45-46. f Proc. Cal. Acad. Sci , 2d Ser., i, p. 48. 
