208 THE CANADIAN NATURALIST. [Vol. vilV 



enormous rock-masses of Silurian limestone holding characteris- 

 tic fossils are widely and abundantly distributed over the first 

 and second prairie steppes. The ascent to the third prarie level 

 which has an avemg-e elevation of from 1,900-2000 ft. above the 

 sea, commences at the Thickwood Hills, 20 miles west of Cartlon 

 and on it tlie limestone boulders do not appear to have reached 

 further west than the longitude of Fort Pitt, and between Pitt 

 and Edmonton not a single boulder of limestoae was observed 

 either along the Saskatchewan River or on the plains. On the 

 Saskatchewan above the the confluence of the Brazeau — a laro-e 

 tributary coming in from the west about mid way between Rocky 

 Mountain House and Edmonton — there are no boulders, and 

 very few pebbles of either granite gneiss or mica schist. At 

 Rocky Mountain House the pebbles and boulders in the drift 

 which is there seen in contact with the coal-bearing rocks, as well 

 as those seen along the river bed are nearly all of either coal- 

 measure sandstone or conglomerate, or of varieties of hard 

 quartzose and siliceous rocks, and though I searched carefully, I 

 did not succeed in finding any of a granitoid or gneisic charac- 

 ter. Small pebbles of grey and whitey-brown limestones holding^ 

 fossils, but too fragmentary for determination, were alsa 

 observed, but by far the larger proportion of the pebbles and 

 boulders in the river at Rocky Mountain House, are composed 

 of the hard siliceous rocks already mentioned, and many of 

 these are traversed by cylindrical forms, having all the appear- 

 ance of the ScoUtlius of the Potsdam sandstone formation. It 

 may 'further be stated that along with the disappearance in 

 ascending the river of the boulders of granitic, gneissic and 

 micaceous rocks, the auriferous character of the drifts likewise 

 dies out, and I was credibly informed that no gold could be 

 found on the North Saskatchewan above Rocky Mountain House, 

 though it had frequently been prospected for by experienced 

 miners. The first gold washings which we saw in descending 

 the river were rather more than forty miles below tho mouth of 

 the Brazeau, and thence to Edmonton, and for some miles fur- 

 ther down, more or less gold has been found on the bars and in 

 the river banks, but always in a very finely divided state, shewing 

 evidence of having been transported from afar. Even as low 

 down as Carlton, gold can, I believe, be found, though not in 

 quantities sufficient to pay for working. On the South Saskat- 

 chewan, at the crossing place about twenty miles S.E.of Carlton, 



