30 HISTORY OF THE 



have been found breeding in numbers on the ishmds in the 

 Arctic Sea; their nests are upon dry ground, near the water's 

 edge; a slight depression worked out to fit the body, with usu- 

 ally a few blades of grass arranged in a circular manner around 

 the edge. Eggs usually three; Ridgway says: ''Eggs two to 

 five, 1.78x1.20; ovate or short ovate, deep olive (varying in in- 

 tensity, however), rather indistinctly spotted or blotched with 

 brown." 



Subfamily STERNINJE. Tekns. 



"Depth of the bill through the angle (symphysis of the lower jaw) less 

 than through the middle of the uostrils; terminal portion of the culmen slightly 

 curved, or nearly straight; mandibular angle seldom prominent. Tail forked, 

 except In Anous (graduated). Size extremely variable, but usually small; 

 never very large." 



Genus STERNA Lixxjius. 



"Size exceedingly variable, the form and colors less so; tail always decidedly 

 forked, and toes almost fully webbed, but the webs concave, or ' scalloped out ' 

 anteriorly." 



Subgenus STERNA. 



Wing less than 12.00; occipital feathers short and blended. Mantle bluish 

 gray; the tail chiefly white; inner webs of quills largely white. (Ridgicay.) 



Sterna forsteri Nutt. 



FORSTBR'S TBRN. 

 PLATE II. 



Summer resident; rare; in migration, common. Arrive from 

 the middle of April to first of May. Begin to return the last 

 of August. 



B. 686, 690. R. 685. C. 798. G. 313, 11. U. 69. 



Habitat. North America generally, breeding from Manitoba 

 southward to Virginia, Texas and California; in winter, south- 

 ward to Brazil. 



Sp. Char. ^' Adult, in summer: Pileum and nape deep black; upper parts, 

 including rump and tail, light pearl gray, the primaries and tail paler and more 

 silvery, the inner webs of the outer pair of rectrices usually darker (sometimes 

 quite dusky) for that portion beyond tiie tip of the next feather. Inner webs 

 of primaries without any well-defined white space, except on two outer quills, 

 but the edge usually more or less dusky. Tips of secondaries, anterior upper 

 tail coverts, sides and upper part of head and neck, and entire lower parts, pure 

 -white. Bill dull waxy orange, the terminal third or more blackish, with the 



