KEEL-BREASTED BIRDS. 245 



under water after their prey (Fig. 280, 3). The common 

 tern (Fig. 280, 2) (Sterna hirundo) is found in Europe and 

 North America. The bill is long, slender, and pointed, 

 the tail long and forked. The nest is a mere depression in 

 the sand, three spotted eggs being laid in each. During 

 the day the sun warms them, the mother performing her 

 office only at night. The roseate tern is a familiar form. 



The Noddy Terns (Anous stolidus) have" a wide geo- 

 graphical range. They are mild and beautiful creatures. 

 At Tortugas they erect rude nests composed of twigs of 

 bay-cedar dropped together upon the bushes, upon the 

 top of which is laid the single, nearly white egg. At St. 

 Paul's Rocks the noddies build a fanciful nest of sea-weed, 

 cemented together and attached to the rock, a lace-like 

 fringe hanging down all around. Upon this platform or 

 bracket the single egg is placed. 



The Laughing Gull (Larus atricilla) * is found upon 

 the tropical and temperate coasts of North America. 



The Arctic Tern (Sterna macrura) is the only suc- 

 cessful enemy of the skua, pursuing it with extreme ferocity. 

 Its eggs are deposited among the stones and mimic the 

 lichen-covered pebbles, this protective mimicry being car- 

 ried out in the downy young. 



The most powerful of the gull family is the skua (Ster- 

 corartus). It has a wide geographical range, the various 

 species being found in the Arctic and Antarctic regions 

 of various countries. 



The Parasitic Jager, of the Arctic region of Eurcpe 

 and North America, follows terns and gulls, forcing them 

 to disgorge their prey. 



The Antarctic Skua (S. Antarcticus) has all the qual- 



* At Tortugas they follow the brown pelican, systematically rob- 

 bing it. When the latter tosses a fish preparatory to swallowing it, 

 the laughing gull with its victorious " Ha-ha ! " alights on its back, leans 

 forward and snatches the morsel and flies away, generally to be robbed 

 in turn by the man-of-war bird (Fig. 283). 



