No. 4.] HUNT — ON CAMBRIAN AND SILURIAN. 425 



maintaining a similar view in 1859, we must notice the history 

 of geological investigation in eastern Canada. So early as 1827, 

 Dr. Bigsby, to whom North American geology owes so much, 

 had given us [Proc. Geol. Soc. I, 37] a careful description of 

 the geology of Quebec and its vicinity. He there found resting 

 directly upon the ancient gneiss, a nearly horizontal dark colored 

 couchiferous limestone, having sometimes at its base a calcareous 

 conglomerate, and well displayed on the north shore of the St. 

 Lawrence at Montmorenci and Beauport. He distinguished 

 moreover a third group of rocks, described by him as a " slaty 

 series composed of shale and graywacke, occasionally passing into 

 a brown limestone, and alternating with a calcareous conglom- 

 erate in beds, some of them charged with fossils * ^' * -i^ 

 derived from the conchiferous limestone." (This fossiliferous 

 conglomerate contained also fragments of clay-slate.) From all 

 these circumstances Bigsby concluded that the flat conchiferous 

 limestones were older than the highly inclined graywacke series ; 

 which latter was described as forming the ridge on which Quebec 

 stands, the north shore to Cape Rouge, the island of Orleans, and 

 the southern or Point-Levis shore of the St. Lawrence ; where 

 besides trilobites, and the fossils in the conglomerates, he noticed 

 what he called vegetable impressions, supposed to be fucoids. 

 These were the graptolites which, nearly thirty years later, were 

 studied, described and figured for the Geological Survey of Ca- 

 nada by Prof. James Hall ; who has shown that two of the spe- 

 cies from this locality were described and figured under the 

 name of fucoids by Ad. Brongniart, in 1828. [Geol. Sur. Canada, 

 Decade II, page 60.] Bigsby, in 1827, conceived that the lime- 

 stones of the north shore might belong to the carboniferous 

 period, and noted the existence of what were called small seams 

 of coal in the graywacke series of the south shore, which sub- 

 stance I have since described in the Geology of Canada [page 

 525.] 



In 1842, the Geological Survey of Canada was begun by Sir 

 William Logan, who in a Preliminary Report to the Government, 

 in that year [page 19], says " of the relative age of the contorted 

 rocks of Point Levis, opposite Quebec, I have not any good evi- 

 dence, though I am inclined to the opinion that they come out 

 from below the flat limestones of the St. Lawrence." He how- 

 ever subsequently adds, in a foot-note, " the accumulation of 

 evidence points to the conclusion that the Point Levis rocks are 



