LARIDAE 



309 



but all have red bill and feet. The colonies of our marsh- 

 breeding species supply large quantities of eggs for eating. 



Of the black-hooded, grey-mantled forms, which have as a 

 rule red bill and feet, L. atricilla, the Laughing Gull, of-the 

 Atlantic coast of North America and Western Mexico, alone has 

 black outer primaries ; this species and L. franklini, of the in- 

 terior of sub-Arctic America, having exceptionally dark mantles, 

 and the latter pinkish under parts. Both migrate south in winter. 



FIG. 62. Great Black-headed Gull. Larus ichthyaetus. x T %. 



L. Philadelphia, Bonaparte's Gull, of all North America, which, like 

 its two following congeners, strays to Britain, has the bill black ; 

 L. melanocephalus, of the Mediterranean and Black Seas, has a jet 

 black head, a partly red bill, and nearly white quills; the very large 

 L. ichthyaetus ranging from the Black Sea and the Levant to Tibet, 

 and wintering in Southern Asia, has the bill almost orange. L. 

 saundersi, a slender-legged stout-billed bird, inhabits the rivers 

 and coasts of China and Mongolia; L. serranus of the Andes 

 from Ecuador to Chili being a near ally. Z. minutus, the Little 

 Gull, frequenting marshy districts in sub- Arctic and temperate 



