348 Dr. George M. Dawson—Glaciation of British Columbia. 
in direction of flow dependent on surface irregularities, in the manner 
described in my report on the northern part of Vancouver Island.* 
No conclusive evidence was here found, however, either in the valley 
of the Stikine River or in the pass leading inland from the head of 
Lynn Canal, to show that the ice moved seaward across the Coast 
Range, though analogy with the coast to the south favours the belief 
that it may have done so. The front of the glacier must have passed 
the outer border of the Archipelago, as at Sitka, well-marked glacia- 
tion is found pointing toward the open Pacific? (average direction 
about 8. 81° W. astr.). It is, however, in the interior region, between 
the Coast Range and the Rocky Mountains proper and extending 
northward to lat. 63°, explored and examined by us in 1887, that 
the most interesting facts have come to light respecting the direction 
of movement of the Cordilleran glacier. Here, in the valleys of 
the Pelly and Lewes branches of the Yukon, traces were found of 
the movement of heavy glacier-ice in a northerly direction. Rock- 
surfaces thus glaciated were observed down the Pelly to the point at 
which it crosses the 186th meridian and on the Lewes as far 
north as lat. 61° 40’, the main direction in the first-named valley 
being north-west, in the second north-north-west. The points 
referred to are not, however, spoken of as limiting ones, for rock 
exposures suitable for the preservation of glaciation are rather infre- 
quent on the lower portions of both rivers and more extended 
examination may result in carrying evidence of the same kind much 
further toward the less elevated plains of the Lower Yukon. Neither 
the Pelly valley nor that of the Lewes is hemmed in by high 
mountainous country except toward the sources, and while local 
variations in direction of the kind previously referred to are met 
with, the glaciation is not susceptible of explanation by merely local 
agents, but rather implies the passage of a confluent or more or less 
connected glacier over the region. 
In the Lewes valley, both the sides and summits of rocky hills 
300 feet above the water were found to be heavily glaciated, the 
direction on the summit being that of the main (north-north-west) 
orographic valleys, while that at lower levels in the same vicinity 
followed more nearly the immediate valley of the river, which here 
turns locally to the east of north. 
Glaciation was also noted in several places in the more mountainous 
country to the south of the Yukon basin, in the Dease and Liard 
valleys, but the direction of movement of the ice could not be 
determined satisfactorily, and the influence of local action is there less 
certainly eliminated. 
Of the glacial deposits with which the greater part of the area of 
the inland region is mantled, it is not intended here to give any 
details, though it may be mentioned that true Boulder-clay is fre- 
quently seen in the river-sections, and that this generally passes 
upward into, and is covered by, important silty beds, analogous to 
1 Annual Report Geol. Surv. Canada, 1885, p. 100 B. 
2 Mr. G. F. Wright has already given similar general statements with regard to 
this part of the Coast of Alaska, American Naturalist, March, 1887. 
