270 NYROCA MARILA 



W. Thompson (1851) and Lilford (1895). The latter said that he had seen them only 

 a few days after capture following persons around a pond for bread and he noticed 

 how loath they were to take food off the surface, seeming not to notice it there at all. 



My Scaup have always moulted later in the summer than all other ducks, in fact, 

 one season I noticed that three males were just beginning to show a change on July 

 23. Before this time they showed no feather loss with the exception of a ring of 

 feathers around the neck, which seems to be the first region affected. 



I used to feed my birds once in a while upon live salt-water minnows {Fundvlus) 

 and they would gulp down fish several inches long with great relish, rising to the 

 surface with them and going through many vigorous head-shakes before they trans- 

 ferred the fish from a crosswise to a lengthwise position in the bill, preparatory to 

 swallowing. 



Hybrids. Crosses between this and other species are rare. Instances have been 

 recorded of crossing with the Tufted Duck, the Red-head (Nyroca americana), the 

 White-eyed Duck and the Golden-eye (Poll, 1911). I know of no instances of its 

 having hybridized in confinement. 



GEOGRAPHICAL RACES 



The geographical forms are poorly marked and it is a question whether any of them is worthy of 

 recognition. The American race, Nyroca marila neurotica, is certainly of very doubtful validity. 

 They are as follows : 



NYROCA MARILA MARILA (Linne) 



Anas marila Linne, Systema Naturae, ed. 12, vol. 1, p. 196, 1766. 

 Nyroca marila Fleming, Philosophy of Zool., vol. 2, p. 260, 1822. 



Characters: Larger than the eastern form, N. m. mariloides; wings of adult males measuring from 

 220-233 mm. 



Range: Europe and northern Asia, but eastern limits not defined. 



NYROCA MARILA MARILOIDES (Vigors) 



Fuligula mariloides Vigors, Zool. Voyage 'Blossom,' p. 31, 1839. 



Fulix mariloides Swinhoe, Proc. Zool. Soc. London, 1873, p. 412. 



Aythia affinis mariloides Stejneger, Bull. U.S. Nat. Mus., no. 29, p. 161, 1885. 



Fuligula marila Auct. (in part). 



Characters: Smaller (with few exceptions); wing of adult males according to Hartert (1920a) 207- 

 220 mm. Also the same writer notices that the black barring of the upper side is coarser thus giving it 

 a darker appearance, which is particularly noticeable on the scapulars. 



Range: Bering Island, and probably Kamchatka and elsewhere. In winter, China and Japan (Hart- 

 ert, 1920a). 



