Vol. XIV 
eae ] OBERHOLSER, Description of a New Empidonax. 
301 
‘ 
colors of the under surface, this most noticeable anteriorly, the 
jugulum and breast having little of the brownish ochraceous 
suffusion so apparent in most specimens of dficilis. The sides of 
neck and head are somewhat grayer, the throat is usually distinctly 
whitish, and the wing-bands appear to be rather more purely 
white. It will thus be seen that while in some characters 
Eimpidonax insulicola is to a certain extent intermediate between 
aificilis and cineritius, yet in the olive brown color above it departs 
equally from both, though not in the direction of either. 
The characters above ascribed to mmsuficola are reasonably 
uniform in the series of five specimens examined. One bird, 
however, from Santa Catalina Island, has the throat rather more 
clearly white, and the upper parts a little lighter and more olivace- 
ous, but these differences are apparently not material. 
So far as it has been possible to ascertain, the only previous 
record of any representative of the genus Hmgidonax from the 
Santa Barbara Islands is by Mr. Eli W. Blake, Jr., who gives 
Empidonax adificilis as common on Santa Cruz Island.! Mr. 
Blake’s #. difficilis is, of course, undoubtedly the &. zmsulicola of 
the present paper. 
For comparison in this connection there have been brought 
together some 85 specimens of Lmpizdonax dificilis, many of them 
taken in the breeding season, this series representing very fully 
the North American range of the species. Among these there are 
very few indeed which can not be distinguished from LAmpzdonax 
msulicola even without comparison, being both lighter and more 
olivaceous on the upper surface, and more deeply yellow beneath. 
A considerable range of variation is, however, exhibited, which is 
not satisfactorily attributable to geographical causes. A specimen 
from Comox, B. C., and another from Parley’s Park, Utah, are 
nearly as dark above as zwsudicola, but are much more yellowish 
olivaceous, and are, moreover, easily distinguished by the very 
deep brownish suffusion on the breast. 
The palest birds examined are from the southwestern border of 
the United States, but with these occur, during the breeding season 
and often in the same localities, some of the darkest birds in the 
1 Auk, IV, 1887, 329. 
