68 PROCEEDINGS OF THE NATIONAL MUSEUM VOL. 95 
the opinion that plebejus should be considered a species distinct from 
ignobilis of South America until there is evidence of closer connection. 
HYLOCICHLA USTULATA SWAINSONI (Tschudi): Eastern Olive-backed Thrush 
Turdus Swainsoni Tscuup1, Fauna Peruana, Aves, 1845, p. 28 (Carleton House, 
lat. 53° N., on the banks of the Saskatchewan River). 
On November 12 I shot an immature male, evidently a bird in 
southward migration, at the edge of a stand of forest above the 
house at Hacienda Santa Maria. 
CATHARUS MEXICANUS FUMOSUS Ridgway 
Catharus fumosus Ripaway, Proc. U. S. Nat. Mus., vol. 10, Aug. 6, 1888, p. 505 
(Costa Rica). 
In the heavy forest near the Hacienda Santa Maria these small 
thrushes were fairly common but were so difficult to see that usually 
I had barely a glimpse of them. They ranged near or on the ground 
in dense shadows and ordinarily managed to slip away when barely 
seen. On November 11 I secured one on the mountain slope back 
of the house. They are thrushlike in action but impressed me as 
somewhat different from Hylocichla. 
The type specimen of this race was taken by Zeledén and has no 
locality other than Costa Rica. It is probable that it came from 
one of the mountains near San José. 
Family SYLVIIDAE 
POLIOPTILA PLUMBEA BAIRDI Ridgway 
Polioptila bairdi Ripaway, Proc. Biol. Soc. Washington, vol. 16, Sept. 30, 1903, 
p. 110 (San Juan del Sur, Nicaragua). 
In brushy areas near Liberia I collected four males and one female 
on October 31 and November 2 and 3 and saw a few others. Their 
mannerisms were typical of gnatcatchers as a group, all being jaunty 
little birds that often are overlooked because of their small size. 
The four males from Liberia all show the white line in the lores 
which, as van Rossem “ has found, marks the winter plumage. This 
white loral line I have observed also in Polioptila plumbea plumbiceps 
Lawrence that I took at the same season of the year at Ocumare de 
la Costa in northern Venezuela, but at the time I did not recognize 
that it was a seasonal character and that in the breeding season the 
lores were black. Hellmayr’s conclusion that these gnatcatchers are 
all geographic races of Polioptila plumbea seems reasonable. 
W Auk, 1931, pp. 34-36, figs. 4, 5. 
18 Proc. U. S. Nat. Mus., vol. 87, 1939, p. 242. 
