CRESTED TERN. 249 



tj; wings, 14; tail, base, 7? ; depth of the fork, 

 J5 T %; tarsus, 1; hind toe and claw, T %- ; middle 

 ditto, 1/0 ; inner ditto nearly 1 ; outer ditto, 1^. 



BLACK- WINGED TERN. 



Sterna melanoptera, SWAINS. 



Bill, feet, and quills, black ; tail forked, longer than the wings, 

 cinereous i the two outer feathers white, with cinereous 

 tips. 



THERE are two or three peculiarities in this species 

 which renders it more easy of discrimination than 

 several of its congeners. Its size is ahout that of 

 S. hirundo ; the bill is particularly straight, so that 

 the commissure has no curve, and the gonys in- 

 clines upwards, just as much as the culmen does 

 downward. The whole upper parts of the head and 

 nape are black; a line of the same colour passes 

 through the eye and lores, leaving a broad white 

 band in front of the head, which passes over the 

 eyes and terminates just beyond them ; the whole 

 of the upper plumage is of a very dark cinereous, 

 paler, indeed, on the interscapulars, but becoming 

 almost black on the whole of the quill-feathers, in- 

 cluding the shafts : the tail is deeply forked, and is 

 coloured like the back, excepting the two outer- 



