CONTENTS. XV 



FAMILY II. LARIN^. GULLS AND ALLIED SPECIES - 469 



Genus I. Lestris. Skua . . . 477 



1. Lestris Catarractes. The Common Skua - 479 



2. Lestris Pomarinus. Pomarine Skua - 487 



3. Lestris Richardsonii. Eichardson's Skua - 492 



4. Lestris parasitica. The Parasitic Skua - 503 



Genus II. Cetospakactes. "Whaxe-Gull - - 506 



1. Cetosparactes eburneus. The Ivory Whale-GuU 508 



Genus III. Rissa. Kittiwake - - - 513 



1. Rissa trydactyla. The Black-footed Kittiwake 515 



Genus IV. Lakus. Gull - - - 523 



1. Larus mai-inus. The Great Black-backed Gull - 526 



2. Larus fascus. The Lesser Black-backed Gull 538 



3. Lai'us argentatus. The Herring Gull - 544 



4. Larus glaucus. The Glaucous Gull - - 557 



5. Larus leucopterus. The White-winged Gull 556 



6. Larus canus. The Green-biUed GuU - - 575 



Genus V. Gavia. Mew . - . 582 



1. Gavia Atricilla. The Leaden-grey-hooded Mew - 585 



2. Gavia ridibunda. The Brown-hooded Mew 593 



3. Gavia capistrata. The Brown-masked Mew - 605 



4. Gavia Sabini. Sabine's Sea-Mew - 607 



5. Gavia Bonapartii. Bonaparte's Mew - - 610 



6. Gavia minuta. The Little Mew - - 613 



7. Rhodostethia Rossii. Ross's Rosy Gull - 618 



FAMILY III. STERNIN^. TERNS AND ALLIED SPECIES 621 



Genus I. Stlochelidon. Steong-billed Tern - 625 



1. Sylochelidon Caspia. The Caspian Strong-billed 



Tern - - - - 626 



Genus II. Sterna. Tern - - - 628 



1. Sterna velox. Ruppell's Tern - - 629 



2. Sterna Cantiaca. The Sandwich Tern - 630 

 ,3. Sterna Hirundo. The Common Tern - 638 



4. Sterna arctica. The Arctic Tern - - 643 



5. Sterna Dougallii. Macdougall's Tern - 648 



6. Sterna minuta. The Lesser Tern - - 652 



