i88 BRITISH SEA BIRDS. 



dozen sub-families, all but one of which are repre- 

 sented at some time of the year on our seaboard. 

 The most important external characteristics of the 

 birds in this family are the peculiar laminated bill, 

 the short legs, the webbed feet, and the dense com- 

 pact plumage. The family is almost cosmopolitan 

 in its distribution. 



NON-DIVING DUCKS. 



Representatives of no less than three of the four 

 sub-families into which the Ducks have been divided 

 by systematists, are found on the British coast-line. 

 Each sub-family contains some thoroughly marine 

 species. We will deal first with the Anatinae, con- 

 taining the Sheldrakes and non-diving Ducks. The 

 birds in this sub-family are distinguished from all 

 others by having the tarsus scutellated or plated in 

 front, and by having only a narrow membrane 

 attached to the hind toe. A peculiarity about these 

 Ducks is that they never dive for their food. This 

 is obtained only in shallow water, by submerging 

 the fore half of the body and dabbling and probing 

 amongst the mud and weeds. In the Sheldrakes 

 the sexes are nearly alike in colour, but in the 

 remaining species there is usually considerable 

 difference in this respect, the males or drakes 

 being handsome, showy birds, the females or ducks 

 brown and comparatively sombre -looking. The 

 Sheldrakes moult once in autumn, the remaining 

 species the same, but the drakes of these latter 



