On the Hybridising of Bucks. 241 



the feathers of the back. On the chest we find a small 

 portioin which in the Mallard is chestnut, quite white, and 

 the feathers bordering this white tract are white with a subter- 

 minal chestnut or brownish spot. The beak is greenish, with 

 a black line along the culmen. 



In the light variety the adult Drake on the back is similar 

 to the form just described, but the feathers are slightly 

 darker and less vermiculated. The tips of the major coverts 

 show traces of ruf ous (Pintail) . The head resembles that of 

 the Mallard, but the ring tends to run up behind the neck. 

 The breast and underparts are pure white, sometimes showing 

 very faint traces of vermiculation on the vent. Under tail 

 coverts dark as in the Mallard. There is a patch of chestnut 

 on either side of the chest, and sometimes faint traces of that 

 colour right across. The flank feathers are boldly vermi- 

 culated, and some of them suffused with rufous (PI. xii., 

 fig. 9). 



Eclipse Plumage. Dark, Variety. The feathers of the back 

 are dark brown, with narrow, irregular, and broken bars of 

 buff, while some of the feathers are pure brown. The back, 

 therefore, as a whole, resembles that of the Pintail in eclipse, 

 but the pure dark brown feathers are common to all three 

 species. The head chiefly resembles that of the Spotbill, but 

 is rather more rufous in colour — a Pintail feature ; there is no 

 trace of Mallard. The chin is white, there is a slight trace 

 of the white ring at the base of the neck, which is curious, 

 seeing it is the eclipse plumage. The feathers of the chest 

 are white, with dark subterminal spots, sometimes forming 

 one or two bars, and a broad buff margin. These spotted 

 feathers, except for their buff margins, are identical with 

 those of the Spotbill, but where the spots have formed into 

 bars and crescents, the feather absolutely matches in colour 

 and markings those found on a Shoveler Drake when coming 

 out of eclipse in November (see PI. xii., fig. 4). The feathers 

 on the remainder of the underparts are white, with dark 

 spots, which closely resemble those on the pure Spotbill, 

 except that the spots are smaller. On the flanks, however, 

 the spots enlarge and coalesce into broad bars, similar, but 

 not so bold, as the bars in the pure Spotbill, and there is also 



