OF THE BEITISH ISLANDS. 349 



Genus CHAULELASMUS, or Qadwalls. 



Type, CHAULELASMUS STEEPEEUS. 



Chaulelasmus, of Bonaparte (1838).— The birds comprising the present 

 genus are characterised by the bill, which is shorter than the head, not very 

 broad, and somewhat compressed, whilst there is no fringe of soft membrane near 

 the tip of the apical portion. The lamellae of the upper mandible are prominent. 

 The central rectrices scarcely extend beyond the rest ; and the speculum is black 

 outwardly and white inwardly. 



This genus is composed of two species, one of which is distributed over the 

 temperate and tropical portions of the Northern hemisphere, whilst the other is 

 confined to the Fanning group of islands. 



The Gadwalls are frequenters of fresh waters rather than coasts and seas. 

 One species is migratory, the other, so far as is known, sedentary. They are 

 birds of rapid and sustained flight. Their notes are harsh and discordant. 

 Their food is partly vegetable and partly animal substances. They are gregarious, 

 especially during the winter, and to some extent social, fraternising with other 

 Ducks. Their nests are rude and made upon the ground, warmly lined with 

 down, and their eggs are numerous and buffish-white. 



