XXI 



GENTTS ALCA. 

 Auk. 

 Alca Torda Razor-billed Auk 



GENUS MERGULUS. 

 Sea Dove. 

 Mergulus alio Common Sea Dove 



GENUS URIA. 

 Guillemot. 

 Uria troile Foolish Guillemot 



" grylle Black " 



FAMILY COLYMBIN^. 

 DIVERS AND GREBES. 



GENUS COLYMBUS. 

 Diver. 

 Colymbus glacialis Great Northern Diver 



" septentrionalis Red-throated •■ 



GENUS PODICEfS. 

 Grebe. 

 Podiceps cornutU3 Horned Grebe 



" Carolinensia Pied bill " 



" cristatus Crested " 



" rubricollis Red-necked " 



