NATATORES. 435 



" The TERNS, or Sea-Swallows, (Sterna,) constitute the fissiros- 

 tral type ; they have remarkably long wings, and slender bills ; 

 the tail is forked; and the plumage, generally, is of a delicate 

 pearl-white, with more or less black upon the head ; the species 

 are numerous, and occur in both hemispheres. The extraordi- 

 nary -genus, Rhynchops,, or Skimmer, although possessing much 

 of the general habits of the Terns, is eminently distinguished by 

 the singular form of its bill, the upper mandible of which is con- 

 siderably shorter than the under, and appears as if one-third of 

 the length had been broken off; three species have been de- 

 scribed, to which we add a fourth ; they skirn over the surface 

 of the ocean with great swiftness, and scoop up small marine 

 insects and other animals. The True or Typical Gull, (Larus,) 

 are a numerous race, dispersed over every clime, and so closely 

 resembling each other in plumage, that many of the species are 

 even now 'but imperfectly understood; they are much like the 

 Terns in general appearance, but the bill is stronger, and the 

 upper mandible is much more curved towards the end ; many 

 are of larger size ; and all, rapacious devourers of fish, and of 

 every marine animal, dead or alive, which is cast upon the shore ; 

 they particularly abound in northern latitudes, but seem to 

 range over the wide world of waters. The Parasitic Gulls, 

 (Lestris,) are the raptorial representative in this family, and are 

 almost confined to cold regions ; they are known by their stronger 

 conformation, their different shaped bill, and the rough scales 

 upon their feet ; these birds, like the frigate cormorants, derive 

 their chief supply of food by robbing their more feeble congen- 

 ers ; they pursue the largest Gulls, and make them disgorge or 

 relinquish their hard-earned prey. The Black-toed .and the 

 Arctic Gulls belong to this group, and both are occasionally seen 

 on the northern shores of Britain." 



FORK-TAILED GULLS. 



The BLACK SKIMMER, Rhynchops, (Gr. rhunchos, beak; ops, 

 face;) nigra, (Lat. black.) This singularly endowed bird (re- 

 ferred to above) is dispersed in large flocks from Texas to New 

 Jersey. It reaches the coast of New York State in May ; breeds on 

 sand beaches or islands ; at night, ascending streams, sometimes 

 to the distance of one hundred miles. The length of the male 

 bird is twenty inches. The bill, for half its length, is a rich 

 carmine, inclining to vermilion ; and the feet are of the same color ; 

 the claws, black. The upper parts are a deep brownish black ; 

 the secondary quills, and four or five of the primaries, tipped 

 with white ; the tail-feathers of the male, are black, broadly 



