178 Brewster, Something More about Black Ducks. [April 



apparently, is Dr. Townsend, who, in the 'Birds of Essex County, 

 Massachusetts' * has much of interest to say about rubripes. His 

 testimony impresses me as being confirmatory, in the main, of the 

 conclusions which I have reached regarding this form, although to 

 his mind it seems to have a somewhat opposite bearing. While 

 avoiding any definite expressions of belief he suggests "for the sake 

 of argument, that rubripes is merely the adult male of obscura." 

 I w r as inclined at first to entertain this theory but it was promptly 

 discarded when the opportunity (mentioned 2 in connection with 

 my original description of rubripes) occurred of comparing the 

 skins of six fully mature, breeding Black Ducks (in the Collection of 

 Mr. Batchelder) from Newfoundland with four from regions border- 

 ing on Hudson Bay. For I found that all the Newfoundland speci- 

 mens were essentially typical of the form then known as obscura, 

 although one of them was an adult male, w T hereas the other four 

 birds were equally good representatives of the form that I named 

 rubripes, although two of them were females. In view of these 

 facts (to which Dr. Townsend does not allude), and of the apparent 

 absence of any counter evidence of a similarly definite kind, I feel 

 justified in maintaining that at present there would seem to be no 

 good reasons for doubting that the large Black Duck with coral 

 red legs, bright yellow bill and spotted throat, which I have called 

 rubripes, is subspecifically distinct from the bird hitherto known 

 as obscura. Nor am I likely to relinquish this conviction until it 

 has been shown to be untenable. If this is ever accomplished it 

 must be either by observation of living birds, reared in confinement 

 from their early youth to full maturity, or by further study and com- 

 parison of specimens collected at the height of the breeding season 

 in definitely known localities. For the examination of any number 

 of Black Ducks of miscellaneous and uncertain ages, shot in autumn 

 and winter in regions where they assemble and intermingle at this 

 time of year after having migrated from unknown summer haunts, 

 is unlikely to ever prove anything conclusively beyond the fact — 

 which I have freely admitted from the first — that rubripes and 

 tristis intergrade. Were it not so they would be distinct species, 

 which I have neither asserted nor believed. 



1 Memoirs Nutt. Orn. Club III, 1905, pp. 125-128. 



2 Auk, XIX, April, 1902, p. 187. 



