^ 1912 J Phillips, The American Black Ducks. 301 



be able soon to obtain experimental proof either for or against the 

 presence of latent Mallard characters in A. tristis. 



Anas wyvilliana — Hawaiian Duck. 



This duck is considered here because of its undoubted relation- 

 ship to the American Black Ducks, and on account of its curious 

 variations, which have already received comments from several 

 writers. I hope to show that, as in the case of the Florida Duck, 

 a certain amount of misconception has arisen because of a failure 

 to understand the sex plumages. There are other matters, however, 

 that cannot be disposed of so easily and which must be taken up 

 in some detail. The U. S. National Museum has kindly loaned 

 seven specimens of this very rare duck, and the three others studied 

 belong to the Museum of Comparative Zoology. The species is 

 now either extinct, or bordering closely upon it. 



The Hawaiian duck is very interesting also, because it shows 

 direct Mallard affinities, and is the only other species except the 

 Laysan Teal (Anas laysanensis) that normally carries the Mallard 

 sex feathers in the tail. Its individual variation is all the more 

 curious when found in a group as stable as the Anatidae, especially 

 when confined to an insular habitat. 



Anas wyvilliana was first described, with a short diagnosis, by 

 Sclater in 1878 (P. Z. S. 1878, p. 250) but there was nothing to 

 show to which sex the specimens belonged, except the mark of the 

 collector, who recorded them as males. In the Voyage of the 

 Challenger (Birds, Plate XXII) Sclater figures one of these males, 

 which is apparently in juvenile plumage or perhaps in summer 

 moult. 



In 1888, Stejneger (Pr. U. S. Nat. Mus., Vol. II, p. 98) calls 

 attention to the defects in the original description and in the plate, 

 and then deals at some length with the various differences found 

 among the five specimens than at hand in the U. S. Nat. Museum. 

 Other remarks were made about this species by T. Salvadori (in 

 the British Museum Catalogue, Vol. XXVII, p. 196, 1895) who 

 also considered this bird more or less of an ornithological puzzle. 



Rothschild in the 'x\vifauna of Laysan,' 1900, p. 271, gives two 

 plates of A. ivyvilliana and discusses his large series of specimens. 



