332 MEMOIRS OF THE NUTTALL ORNITHOLOGICAL CLUB. 



Lexington, Arlington, Belmont, Watertown and Waltham, and we continue to 

 see its golden-yellow plumage and to hear its simple yet attractive song in many 

 parts of Cambridge. But in these, as in most other localities which have 

 become infested with English Sparrows, the Summer Yellow-bird has been 

 diminishing in numbers for twenty years or more. 



Yellow Warblers are seldom seen in Massachusetts after the middle of Sep- 

 tember, but I have a young male which Mr. S. W. Denton shot in our garden in 

 Cambridge on November 28, 1891. As I have already said in another connec- 

 tion, the coloring of this specimen is so peculiar and so closely similar to that of 

 the Orange-crowned Warbler that Dr. J. A. Allen, Mr. D. G. Elliot and Mr. F. 

 M. Chapman are inclined to consider the bird a hybrid between H. cclata and D. 

 (Bstiva. Mr. Robert Ridgvvay, however, agrees with me in believing it to be an 

 unusual example of the latter species, possibly representing some geographical 

 race not as yet recognized or, perhaps, merely an abnormal phase of plumage. 

 Its upper parts are dull, grayish olive-green, brighter and more yellowish on the 

 rump and upper tail coverts. The under parts are pale yellowish olive, nearly 

 uniform everywhere sa\'e on the throat, which is dull ashy faintly tinged with 

 yellowish. The outer two pairs of tail-feathers have a narrow edging of yellow 

 on their inner webs, and the greater and middle wing coverts are tipped and 

 edged with greenish olive, forming two obscurely defined wing bars. In 

 respect to all its structural characteristics, and also in size, the bird agrees 

 perfectly with D. cBstiva. 



203. Dendroica caerulescens (Gmel.). 



BLACK-THRO.'iTED BlUE VVaRBLER. 

 Rather common transient visitor in spring and autumn. 



SEASONAL OCCURRENCE. 



May 5, iSg6, one seen, Arlington, W. Faxon. 



May 10 — 25. 

 Jime 3, 1S90, one male heard, Cambridge, W. Brewster. 



August 26, 1895, one ad. male seen, Cambridge, W. Brewster. 



September 20 — October 10. 

 November 3, 1904, one male seen, Cambridge, G. M. Allen. 



The Black-throated Blue Warbler visits the Cambridge Region very regu- 

 larly at its seasons of migration, but seldom in any considerable numbers. As a 



