COMMON TERN. 



WILSON'S TERN. SEA SWALLOW. SUMMER GULL. MACKEREL 



GULL. 



Sterna hirundo. 



Char. Mantle deep pearl gray; crown and nape black; rump and 

 tail white; beneath, pale gray, shading to white on the throat; bill and 

 legs orange red. Tail deeply forked. Length 13 to 16 inches. 



In winter the under parts are pure white, and the crown is mottled 

 with white. 



The young birds have bars of brown on the mantle, and the crown is 

 of a brownish tinge ; also, the bill and legs bear a yellow tinge in sum- 

 mer, and turn to nearly black in winter. 



Nest. On the sand or amid shingle or short herbage near water, — 

 a slight depression, sometimes sparsely lined with grass or weeds; occa- 

 sionally a rather bulky nest is made of straw or sea-weed. 



Eggs. 2-5 (usually 3); the ground color varies, olive and buff tints 

 prevailing; the marking also varies, but is always profuse and of several 

 shades of brown ; the size averages about 1.60 X i-i5- 



The Common Tern is an inhabitant of both continents, 

 being met with on the coasts of most parts of Europe as far 



