66 THE ROYAL SOCIETY OF CANADA 



line to the Yukon. Selwyn^ first recognized these rocks as a unit in 

 the Cordillera and although he applied no specific name to them he 

 stated that they were the oldest rocks observed in the country but did 

 not place them in any geological period. 



G. M. Dawson^ in his report on the geology of West Kootenay 

 district gave the name "Shuswap series" to a similar group of rocks 

 exposed on the western shore of Kootenay Lake which he correlated 

 with the series of schists, limestones, and gneisses occurring around 

 Shuswap Lake. He regarded the Shuswap series as Archaean in 

 age, although no evidence of an unconformity with the overlying 

 series could be detected. 



The Shuswap series in the vicinity of the Fraser River from Tête 

 Jaune Cache to Fort George was examined by Malloch,^ who expresses 

 some doubt concerning their Archaean age in the following words, "the 

 author suggests an alternative hypothesis, that the schists and 

 gneisses are the metamorphosed equivalents of the grey quartzites 

 which occur in the Castle Mountain series." The Castle Mountain 

 series is of Cambrian age. 



In 1912, Daly,"* in studying the geology along the 49th parallel 

 of latitude came to the conclusion that the rocks mapped on the West 

 Kootenay map-sheet (No. 792) by Brock and McConnell as belqnging 

 to the Selkirk series of Cambrian or Cambro-Silurian age, are Archaean, 

 applying the name Priest River terrane and correlating this terrane 

 with the Shuswap series of Dawson. Daly states that the Priest River 

 terrane is overlain unconformably by the Summit series, the lower 

 part of which he places in the Beltian. 



In 1913, the original Shuswap area of Dawson around Kootenay 

 Lake was examined by the author,^ who showed that the rocks mapped 

 as Shuswap were Beltian or post-Beltian since they proved to be 

 metamorphosed equivalents of the Purcell series and later rocks. 

 These rocks exposed around the shore of Kootenay Lake strike in the 

 direction of those mapped as Priest River terrane and are equiva- 

 lent to the Shuswap by Daly.^ 



Drysdale^ who restudied the Priest River terrane came to the 

 following conclusions: "The Priest River terrane instead of being 

 Archaean is considered to be Beltian and simply the hydrothermally 



1 Selwyn, A. R. C, Geol. Surv., Can., Rept. of Prog., 1871-72. 



2 Dawson, G. M., Geol. Surv., Can., Ann. Report., vol. IV, 1889. 



3 Malloch, G. S., Geol. Surv., Can., Sum. Rept., 1909. 

 * Daly, R. A., Geol. Surv., Can., Mem. 38, 1912. 



6 Schofield, S. J., Geol. Surv., Can., Sum. Rept., 1913, p. 136. 



6 Daly, R. A., Geol. Surv., Can., Mem. 38, 1912, p. 258. 



^ Drysdale, C. W., Geol. Surv., Can., Sum. Rept., 1916, p. 61. 



