76 



FOREST TREES OF THE PACIFIC SLOPE. 



Liard, and Francis rivers nearly to Finlayson Lake (lat. 61° 35'). Locally noted on 

 Francis Lake, Francis River at mouth. Reappears in central Alaska (long. 145° 45' to 

 158° 40') in valley of lower Yukon, upper Koyokuk, Tanana, and Upper Kuskokwim rivers, 

 extending north to latitude 67° on Koyukuk River and south to headwaters of Kuskokwim 

 River (lat. 63°) ; extends from river valleys to 1,650 feet. Locally noted on Yukon from 



Fig. 28a. — Larix alaskensis: a, fruiting branch; b, back of cone scale; c, a cone scale 

 with ovules ; d, bract of cone scale — enlarged ; e, bract of cone scale of Larix ameri- 

 cana — enlarged. 



Kaltag near Norton Bay (long. 158° 40/ at least up to mouth of Tanana; Minook Creek 

 (southern tributary Yukon above Tanana) ; upper Koyukuk River from Bettles down at 

 least to Bergman ; Tanana River and tributaries as follows : Main valley, one patch be- 

 tween Goodpastor and Salcba rivers (lat. 145° 45', east limit now known), Salcha 

 River, two patches on small tributaries ; Cantwell River, one patch on east side near 



