NESTS AND EGGS OF NORTH AMERICAN BIRDS. 169 



682. Elegant Tern — sterna elegans. The nesting and eggs of this 

 elegant species are the same as those of the Royal Tern and the birds also 

 resemble each other. Princely Tern is its other name. 



Hab. Pacific coast of America from California to Chili. 



683. Cabot's Tern — sterna cantiaca acuflavida. Varying from 

 white to buff, irregularly spotted and blotched with brown, umber, bluish 

 and reddish; rather pointed; two or three in number; size about 2.10 by 

 1.40. The beautiful Sandwich Tern has an extensive distribution in both 

 Hemispheres; in North America it has been observed as far north as 

 Southern New England. Breeds in large colonies, like most of the terns, 

 depositing the eggs in the dry sand. It nests on the small sandy islands 

 off the coast of Cape Sable in the latter part of June. Breeds commonly 

 on the coasts of Central America, and on some of the larger West India 

 islands. 



Hab. Tropical America, northward along the Atlantic coast, irregularly, to Southern New England. 



685. Forster's Tern — sterna forsteri. Varying from nearly pure 

 white and pale green to warm brownish-drab, irregularly spotted and 

 blotched with brown, umber and lilac; two or three are the number laid; 

 size 1.85 by 1.35. Forster's Tern is distributed throughout North America 

 generally. It is abundant along the Atlantic coast during the migrations. 

 Breeds from Manitoba southward to Virginia, Illinois, Texas and Cali- 

 fornia, depositing its eggs on the ground in marshes. In winter it is found 

 southward to Brazil. 



686. Common Tern — sterna fluviatilis. Varying from greenish to 

 deep brown, spotted and blotched with brown, blackish and lilac; two 

 to four, and very rarely five, commonly three; the eggs are not distin- 

 guishable from those of allied species. The variations in ground-color and 

 markings are so great that the only positive means of distinguishing them 

 when breeding in colonies with other species is by watching the bird flying 

 to or from its nest, or in some way capturing it. Mr. Capen, in "Oology 

 of New England," figures specimens that may be taken as faithful repre- 

 sentations of either the Arctic or Roseate Terns. Size about 1.70 by 1.25. 

 Sea Swallow breeds in various localities throughout its North American 

 range. Along the New England coast the period of incubation com- 

 mences about the first of June. Mr. Worthington informs me that on 

 Gull and Plum Islands fresh eggs can be found from the loth of June to 

 the middle of July, and that he never saw but one set of more than four 

 eggs in the thousands he has collected. He says the nests are always 

 placed on the ground or rocks, and they are made of a few pieces of grass 



