st.johx.] PALAEOZOIC AEEAS PEIMOEDIAL. 481 



For convenience of reference the lower limestone horizons of the 

 above section are designated by the terms upper and loiver Quebec, by 

 which it is not intended to convey the impression that these beds repre- 

 sent or are the equivalents of the earlier and later depositions during 

 the Quebec epoch, — a determination for which paleontological evidence 

 is at the present time wanting, but which will be of use hereafter in re- 

 calling these quite persistent calcareous horizons. 



PEIMOEDIAL QUAETZITES. 



In the extreme southwest portion of the district a narrow tongue of 

 the Huronian (?) quartzites of Mount Putnam extends down to Eoss 

 Fork, but it is so obscured by denudation and later deposits as scarcely 

 to be regarded as an element in the present stratigraphic history of the 

 district. Indeed the basis quartzite of the present series, or Potsdam, 

 does not present a fair exhibition in this quarter within the limits of our 

 territory at the points visited the present season. But on the north- 

 eastern flank of Mount Putnam, the high northern culminating peak of 

 the Portneuf Eange, occurs a considerable thickness of dark, rusty-red 

 sandstone, finely laminated below, presenting a much broken up expos- 

 ure resting upon the heavy quartzite, which latter runs up into the crest 

 of the mountain. This rusty quartzitic sandstone may represent the 

 Potsdam in this quarter, but the immediately superimposed deposits 

 associated with this ledge are so obscured as to give no clew as to their 

 character. 



We do not again meet with authentic exposures of this horizon until 

 reaching the Teton Eange. Here they were studied by Professor Brad- 

 ley, who ascribed to the inferior " very compact ferruginous quartzite" 

 a thickness of 50 to 75 feet. Overlying the latter occurs a space of 200 

 feet or more hi which appear white and reddish laminated quartzitic 

 sandstones, usually evenly bedded, but the exposures are obscure in the 

 slopes below the forks of West Teton Creek where they were examined 

 last summer. But higher up on the mountain Professor Bradley had 

 opportunity to examine this horizon in the free slopes of the high Alpine 

 ridges, where they show " about 300 feet of partly compact and partly 

 shaly glauconitic sandstones, which are evidently equivalent to the so- 

 called Knox sandstones of Safford, which form, in Tennessee, the lower 

 part of the Quebec Group." Professor Bradley observed no fossils in 

 these beds, and he was of the impression that they are "unequally dis- 

 tributed," though, so far as could be determined, they constitute a per- 

 sistent element in the stratigraphy of this region. 



The same set of deposits evidently occurs in the Gros Ventre Eange, 

 also in the Bufialo Fork Peak uplift. In both these localities the inferior 

 conglomeritic laminated quartzite and quartzitic sandstone are associated 

 with interlaminations of a beautiful white quartzite in which the grains 

 of silica often have the appearance of the roe of fishes. In the Gros 

 Ventres the quartzite was seen in immediate contact with the uncon- 

 formable Arclnean schists, from which it is separated by a handsome 

 rose-colored, finely -laminated, gneissose lamina, which may be the meta- 

 morphosed inferior layer of the quartzite. The overlying portion is 

 made up of rusty indurated layers and dirty-yellow deposits, which, how- 

 ever, do not reach the same thickness as reported in the Teton Eange. 



CANADIAN. — QUEBEC GEOITP. 



The identification of rocks of the age of the Quebec Group, in this 

 northwestern region, I believe, was based upon materials brought in by 

 31 as 



