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Genus CLANGULA. 



Anas apud Linnaeus, Syst. Nat. i. p. 199 (1766). 

 Clangula, Boie, Isis, 1822, p. 564. 

 Fuligula apud Bonaparte, Synop. p. 393 (1828). 

 Glaucion apud Kaup, Natiirl. Syst. p. 53 (1829). 

 Bucephala apud Baird, B. of N. Am. p. 795 (1858). 



In this genus only three species are included, all of which are found in the Western Palsearctic 

 Region, two being resident, and the third only a rare straggler from the Nearctic Region. They 

 are, as a rule, marine species, except during the breeding-season, when they are often found far 

 inland. They swim well and buoyantly, except when alarmed, when they submerge their body 

 so that only the back is visible above the surface ; and they dive so rapidly that they will dive at 

 the flash when fired at. They obtain their food chiefly under water, and are able to dive very 

 deep and to remain for a long time below the surface. Their food consists of crustaceans, small 

 water-insects, fish, and aquatic vegetable substances. Their flight is very rapid and direct, their 

 stiff sharp wings producing a whistling sound as they pass rapidly through the air. 



They breed in holes in trees — except Clangula islandica, which breeds where there are no 

 trees, and makes use of holes in walls or heaps of stones. The eggs, which are numerous, are 

 deposited on a bed of down at the bottom of the hole, and are dull greenish-grey in colour, and 

 rather glossy and smooth in texture of shell. 



Clangula glaucion, the type of the genus, has the bill shorter than the head, higher than 

 broad at the base, depressed towards the tip, which is rounded and not broader than the base ; 

 unguis large, broadly elliptical, decurved at the tip ; nostrils large, oblong, placed in the anterior 

 part of the nasal sinus ; upper mandible much overlapping the lower one, concealing the ends of 

 the lamellae ; trachea enlarged about the middle, having at the lower end a large bony mem- 

 branous dilatation ; wings moderately long, pointed, the first quill longest ; tail rather long, 

 rounded ; legs short, placed far aft ; tarsus anteriorly scutellate ; hind toe slender, broadly lobed ; 

 anterior toes long; interdigital membranes full; claws moderate, rather obtuse, that on the 

 middle toe curved outwards, internally expanded and rounded. 



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