326 OBERHOLSER, Notes on N. A. Birds. II. fuk 
cerulescens, basing this statement on two adult males which seem 
to be nearer that form. In this region, which is the transition 
ground between many northern and southern races, particularly 
those of the Allegheny Mountains, we should expect to find speci- 
mens that would give more or less trouble in their identification, 
and this is true not only in the particular species under considera- 
tion but in several others. There are in the Biological Survey 
collection 9 adult specimens of the Black-throated Blue Warbler 
from the mountains of western Maryland, taken at Finzel, Bittinger, 
and Kearney. This series includes both males and females, and 
while some of the specimens incline strongly toward Dendroica 
cerulescens cerulescens, and all of them are more or less intermedi- 
ate, the series as a whole shows that the breeding form of this 
region is Dendroica cerulescens cairnsi. 
Vermivora celata orestera Oberholser. 
The Rocky Mountain form of Vermivora celata was originally 
described ! from Willis in northern New Mexico. Most subsequent 
authors, doubtless from lack of sufficient material, have failed to 
recognize its distinctness. Additional material from various parts 
of its range, examined since the original description was published, 
fully substantiates the characters of the race as they were given. 
It is readily distinguishable from Vermivora celata celata by its 
larger size and much more yellowish coloration both above and 
below; and from Vermivora celata lutescens by its much greater 
dimensions and by the duller, less yellowish color of both upper 
and lower parts. Thus, while Vermivora celata orestera is inter- 
mediate in the character of its coloration between Vermivora celata 
celata and Vermivora celata lutescens, it is not so in size, for it is 
larger than either. It occupies much the same relation to the 
eastern and western races of its species as does Wilsonia pusilla 
pileolata to Wilsonia pusilla pusilla and Wilsonia pusilla chryseola. 
Detailed measurements of this and the other forms of Vermivora 
celata may be found in the present writer’s previous paper on the 
subject. 
1 Vermivora celata orestera Oberholser, Auk, XXII, July, 1905, p. 243. 
2 Auk, XXII, April, 1905, pp. 246-247. 
