EOSS ON MAMMALS, ETC. OP THE MACKENZIE ElVEB DISTRICT. 289 



No. of Species. 



Family Laridce. 



(Lestridinse.) 



Genus Stercorarius. 



170. Stercorarius pomarinus (Temm.). Pomarine Skua. Slave 



Lake : very rare. 



171. Stercorarius parasiticus \\ (Temm.). Arctic Skua. North to 



Fort Simpson : rare. 

 tl72. Stercorarius parasiticus, var. Eichardsonii. Slave Lake : rare. 



173. Stercorarius catarraches (Temm.). North of Slave Lake: very 



rare. 



174. Stercorarius Gepphus \\ (Bru.). Buffon's Skua. North to 



Lapierre's House : rare. 



(Laridae.) 

 Genus Larus. 

 "I'175. Larus glaucescens\\ (Light.). Glaucus-winged Gull. Slave 



Lake : abundant. 

 1 176. Larus argentatus \\ (Brii). Herring Gull. North to Arctic 



coast: abundant. 

 tl77. Larus californicus (Lawr.). California Gull. Slave Lake : 

 abundant. 



Genus Chroicocephalus. 



178. Chroicocephalus Philadelphia (Laur.). North to Fort Simpson : 



not rare. 



Genus Hissa. 



179. Missa septentrionalis \\ (Laur.). Slave Lake : very common. 



(Sterninse.) 

 Genus Sterna. 

 flSO. (S'^ernffl caspj'a (Pallas). Caspian Tern. Slave Lake : rare. 

 fl81. Sterna Wilsonii \\ (Bon). Wilson's Tern. Slave and Bear 



Lakes : very rare. 

 fl82. Sterna macroura\\ (Naum). Arctic Tern. Bear Lake: 

 abundant. 



Genus Hydrochelidon. 



183. Sydrochelidon plumbea (Wilson). Short-tailed Tern. Slave 



Lake : rare. Numerovis other species of the sub-family 

 Lariaae doubtless exist in this district ; and will appear by 

 degrees as the collections increase. 



Family Colymhidce. 



(Colymbinse.) 

 Genus Colpnbus. 



184. Colymlus torquatus || (Brii). Loon. North to Arctic coast : 



abimdant. 



185. Colymbus Adamsi.\\ North to Great Slave Lake : abundant. 

 |186. Coly mbus arcticus \\ (Linn.), var. Pacificus. To Arctic coast: 



rather rare. 



