BIRDS OF THE CAMBRIDGE REGION. lOI 



The adult males were in fully mature plumage, and Mr. Deane got sufficiently 

 near them to make out all their characteristic markings with absolute certainty. 

 Up to within the past five or six years I have found the American Mer- 

 ganser regularly, and during some seasons abundantly, in March and April, on 

 the flooded meadows along Concord River, all the way from Wayland to Bed- 

 ford, but the instances above mentioned are the only ones definitely known to 

 me of its occurrence in the Cambridge Region. 



17. Merganser serrator (Linn.). 

 Red-breasted Merganser. Sheldrake. 



Uncommon transient visitor in late autumn. 



SEASONAL OCCURRENCE. 



November 17, 1900, one seen, Fresli Pond, O. A. Lotlirop. 

 December 29, 1866, one ad. male seen, Fresh Pond, W. Brewster. 



As the Red-breasted Merganser is of regular and very common occurrence 

 in Boston Harbor during autumn, winter and early spring, one would suppose 

 that, like the Whistler, it would also frequent the Back Bay Basin, but Mr. 

 W. A. Jeffries has never known it to alight there although he occasionally sees 

 small flocks passing and repassing rather high over the water. 



On December 29, 1 866, I noted a solitary bird in Fresh Pond, where it was 

 swimming close under the steep northern shore of Hemlock Point ; as it was a 

 male in fully mature plumage, and at one time within a few yards of me, there 

 can be no question as to the correctness of my identification. 



Mr. O. A. Lothrop is equally sure that two adult male Sheldrakes which he 

 saw together in this pond on November 24, 1 897, and a single bird which he 

 found there on November 17, 18, 28, and 30, 1900, were Red-breasted Mer- 

 gansers. I also learn from Mr. John H. Hardy, Jr., that he has killed represen- 

 tatives of this species in Spy Pond and in the Mystic Ponds. 



