21 A Brewster om an apparently Ne-w Gull. [October 



ON AN APPARENTLY NEW GULL FROM 

 EASTERN NORTH AMERICA. 



BY WILLIAM BREWSTER. 



In a recent issue of this Bulletin* I recorded a supposed speci- 

 men of Larus glaucesce7ts^ from the Bay of Fundy, and Mr. 

 Merrill, on the same page, announced another captured near 

 Grand/Menan. At that time neither bird had been compared 

 with typical specimens of glaucescens, but both agreed so well 

 with descriptions, especially in the peculiar "washed out" 

 appearence of ihe primaries (a character said to be diagnostic 

 of glaucescens) that there seemed to be no reason for doubting 

 that they really belonged to that species. Moreover, there was 

 nothing at all improbable in the occurrence of glaucescens on the 

 coast of New England, for Kumlien had reported it as breeding 

 at Cumberland Sound,! whence it would be likely to follow the 

 Atlantic Coast in its migrations southward. At least so I rea- 

 soned at the time, but, as will presently appear, there was more 

 than one hidden flaw in the evidence upon which my conclusions 

 were based. 



Shortly after the publication of the notes above mentioned, 

 Mr. Merrill was kind enough to send me his specimen for exam- 

 ination, and at about the same time another, of which I had not 

 previously known, was received from Mr. Everett Smith. Find- 

 ing that both were similar to Mr. Welch's bird (the Bay of Fundy 

 specimen), and that all three had certain peculiarities not ascribed 

 to glaucescens^ I determined to investigate the matter further and 

 to this end applied to the National Museum for the loan of an 

 adequate series. Through Professor Baird's and Mr. Ridgway's 

 kindness this series was promptly forwarded, and is now before 

 me. It includes several typical glaucescens^ both adult and im- 

 mature ; one of Kumlien's supposed glaucescens from Cumber- 

 land Sound (the only one brought back by him, or at least in the 

 National Collection, I understand) ; ''and some examples of L. 

 leucopterus. In addition to these specimens I have been able to 



* Vol. VIII, No. 2, April, 1883, p. 125. 

 t Contrib. to Nat. Hist. Arc. Am., pp. 98, 99. 



