CLASS TI. AVES: ORDER 8. NATATORES. 



341 



THE TROPIC BIRD. 



within the tropics ; many of them breed on the rocky islands at the east end of Porto Rico, and 

 some on the Bermudas. They feed entirely on fish, which they capture by descending upon 

 them and seizing them in their bills. The Smithsonian Catalogue mentions the Yellow-billed 

 Tropic Bird, P.flavirosfris, found in the tropical regions of the Atlantic seas. There are sev- 

 eral other species in the Indian and Pacific Oceans. 



THE LARID^ OR GULLS. 



This family includes the Terns or Sea-Swallows, the Shearwaters, and the Trtie Gulls. 



All 



these birds have long wings, fly with great ease, and spend a great part of each day in liovering 

 over the sea, generally along the shores, in search of food. They often sit on the water, where 

 they arc very buoyant, but they swim little, and are incapable of diving. They are active, noisy 

 birds, mostly living on small fish, which they capture in skimming over the water. 



Genus STERNA : Sterna. — This includes several species of Tern. The Common Tern of 

 Europe, ^S*. hirundo, is fourteen inches long; ash-gray above, beneath white; builds sometimes on 

 rocky and sometimes on low, flat, sandy islands, but always near the sea ; eggs two, of a yellowish 

 stone-color. Like the swallows of the land, it flies with great ease, and is almost the whole day on 

 the wing, noisy, and restless, performing various graceful evolutions in the air, yet constantly 

 looking out for the small fish on which it feeds. This species is chiefly confined to the seas of Eu- 

 rope ; in winter it migrates to the southern latitudes. 



Other species are as follows: the Arctic Tern, S. Arctica ; found in Europe and America; 

 the Whiskered Tern, S. Icucojmrcia, found in Europe : the Gull-billed Tern, S. Anglica ; found 

 in Europe and North America : the Marsh Tern — S. aranea of Wilson ; found on our Atlantic 

 coast: the Lesser Tern, S. minuta, a very elegant species; found in Europe, India, and the 

 United States : the Black Tern, S.fissipes, common in Europe and America : the White-winged 

 Tern, S. leiicoptera, a handsome species with a long tail ; found in Europe ; the Sooty Tern, S. 

 fuUffinosa, possessing a remarkable power of flight ; found in Europe, Asia, Australia, and America; 

 and the Roseate Tern, £J. Douglassi ; found in Europe and America. 



