LARID.E. 559 



above tlie other. The upper mandible is considerably 

 shorter than the lower one, which consequently 

 projects to some distance beyond it. The wings are 

 long and pointed, indicating great power of flight, 

 and the tail is forked. These birds are peculiar to 

 the tropical parts of both hemispheres. They prefer 

 the sheltered inlets and estuaries of rivers, over the 

 smooth water of which they fly, near the shores at 

 the flood-tide, seeking for small fish and molluscous 

 animals. These they obtain by skimming the sur- 

 face of the prolific sea with their lower mandible, 

 while the upper one is kept out of the water. Their 

 flight is swift and undulating. When on the ground, 

 they walk very awkwardly, and though they possess 

 webbed feet, they rarely swim or even float on the 

 surface of the water. During the day, they collect 

 in flocks on the isolated shoals left bare by the re- 

 cess of the tide. When the breeding season comes, 

 they visit the low sand-bars and dry flats of the 

 coast, for the purpose of scratching out a slight 

 hollow in the sands, wherein the female usually 

 deposits three eggs. The female only sits on the 

 nest during the night, or in wet and stormy weather. 

 The young are scarcely distinguishable from the 

 sand, on account of the similarity of their colour ; 

 and before they leave the nest may often be seen 

 basking in the sun, and spreading out their wings 

 upon the warm beach. 



The type of this sub-family, — 



The Black Slsimmer (RhT/nchojJs iiigra), is an inhabitant 

 of the coasts of America, from the Straits of Magellan 

 to the United States. It is about nineteen inches long, 

 black above and white beneath, with a white band on 

 each wing ; the bill and legs are red. Supported by its 

 long and pointed wings, which sometimes extend fully 

 forty inches, the Skimmer darts swiftly over the surface 

 of the ocean, dipping the extremity of its curious bill into 

 the water as it moves along, for the purpose of capturmg 

 the small fishes and Crustacea upon which it feeds. " This 

 truly singular bird is the only sj^ecies of its tribe hitherto 



