10 CHECK LIST OF THE 



zontal ; hind toe small and elevated (wanting in Rissa). Bill usually long, 

 horny, not serrate, nor lamellate ; no gular pouch. Wings very long and 

 pointed ; tail well developed. Water birds, of great powers of flight ; 

 feeding on fishes and floating garbage. 



FAMILY STERCORARIIDiE. (THE J^GERS.) 



Gull-like birds with the bill hooked and cered ; tail square with the 

 middle pair of feathers long-exserted ; tibia naked below; tarsus scutel 

 late in front, granular behind. Voracious birds, which frequently live 

 by tormenting the Gulls and Terns and compelling them to disgorge 

 their food. Plumage dark above. 



GENUS STERCORARIUS. 



(*) (36) Pomarine Jaeger. 



(Stercorarius pomarinus.) 

 An occasional visitor to the great lakes. 



(37) Parasitic Jaeger. 



(Stercorarius parasiticus.) 

 An occasional spring and autumn visitor to the great lakes. 



FAMILY LARID^E. (THE GULLS.) 



Long-winged swimmers. Bill long, horny, not serrate nor lamel- 

 late ; no gular pouch. Feet palmate ; tibia feathered ; legs near centre 

 of equilibrium ; hind toe elevated, small (wanting in Rissa). Wings very 

 long and pointed. Tail well developed. General colour usually white, 

 with a darker mantle of a slaty bluish tint and commonly some black mark- 

 ings. Sexes alike in colour, but the plumage varying very much with 

 age and season. Possessed of wonderful power of flight. Food, fishes 

 and floating garbage. The birds are the scavengers of the waters. 



GENUS PAGOPHILA. 



(*) (39) Ivory Gull. 



(Pagophila alba.) 



A regular but not a common winter visitor to Lake Ontario. It prob- 

 ably occurs on the northern lakes also, but as yet I have not heard of it. 



GENUS RISSA. 

 (40) Kittiwake Gull. 



(Rissa tridactyla.) 

 A regular, but not common, winter visitor to the great lakes. 



