INTEODUCTION. 



33 



Four fur traders liviug at Fort Yukon in 1875 or 1876 told me that the weather was intensely 

 cold there for two mouths, and that for six weeks a small bottle of mercury hanging on a project- 

 ing log at the corner of the cabin was frozen solid most of the time. Mr. W. H. Dall once saw 

 the thermometer standing at +112° at Fort Yukon in summer. From this same explorer I quote 

 the following average temperatures for Nula'to and Fort Yukon. Both these stations are in the 

 midst of this district, and Fort Yukon lies under the Arctic Circle : 



I 



Mean temperatures. Nulato. FortTukon. 



bpriug . . 

 Summer 

 Autamn 

 Winter . 



+29.3 

 +60. 0? 

 +36. 0? 

 -14.0 



■14. 22 

 -59 67 

 -17. 37 

 23. 80 



In a brief meteorological record kept for me in 1880-'81 at Fort Reliance (the point where the 

 Yukon crosses the British boundary line), by Mr. L. K McQuesten, I find the lowest winter tem- 

 peratures were —65° and —67° on the 19th and 20th of November, 1880, but the thermometer 

 recorded —50° and lower several times afterwards during that season, with long periods of minus 

 temperatures. On May 16, 1881, the temperature arose to +58° and the ice in the Yukon broke 

 up and began to move down. 



Among other plants recorded from the Yukon by Dall are mentioned red and black currants, 

 gooseberries, cranberries, raspberries, thimbleberries, salmon-berries, killikinik berries, blueberries, 

 bearberries, twinberries, dewberries, service-berries, mossberries, and the fruit of Rosa cinnamomea; 

 certainly an abundance of small fruits. 



The species of birds and mammals found in this district, and distinguishing it from the other 

 faunal areas of Alaska, are numerous. 



The mammals having their Alaskan center of abundance here and occurring rarely or very 

 much less numerously elsewhere in Alaska are — 



Lynx canadensis. 



Cams' occidentalis (the black variety). 



Vulpesfulvus argentatus (Black Fox). 



Mustela americana. 



Gulo luscus. 



Lutra canadensis. 



Ursus horribilis. 



Ursus richardsoni. 



Ursus americanus. 



Sciurus Imdsonius. 



Arctomys pruinosus. 



Castor canadensis. 



Synaptomys cooperi. 



Erethizon dorsatus epixantlms. 



Lepus americanus americanus. 



Lagomys princeps. 



Alces americana. 



Bangifer tarandus (a large dark variety). 



Ovis montana dalli. 



Among birds, the following species appear to have their center of abundance in this district : 

 Parus cinctus ohtectus. 



Parus atricapillus turneri. 

 Parus hudsonicus. 



Perisoxens canadensis fumifrons. 

 ■ Picoides americanus alascensis. 



The birds common in other parts of the north, but not found in the other districts of Alaska: 



Turdus aliciw. 

 Merula migratoria. 

 Cinclus mexicana. 

 Relmintliopliaga celaia. 

 Dendroica coronata. 

 Dendroica striata. 

 Seiurus noveboracensis. 

 Ampelis garrulus. 

 Clivicola riparia. 

 B. Mis, 156 5 



Loxia ourvirostra minor. 

 Loxia leucoptera. 

 Zonotrichia intermedia. 

 Junco hyemalis. 

 Passerella iliaca. 

 Pica pica Imdsonica. 

 Perisoreus canadensis. 

 Sayornis saya. 

 Contopus borealis. 



