G. M. Dawson — Geology of British Columbia. 217 



mon to it and to the Dakota group of the Middle Cretaceous of the 

 interior region of the continent. The botanical evidence, while yet 

 imperfect, is therefore by no means in contradiction to that afforded 

 by the animals and the stratigraphy. 



A number of fossils from the Queen Charlotte Islands have also 

 been described and figured ' from Mr. Eichardson's collections made 

 during a visit to the islands in 1872. Additional collections made by 

 the writer in 1878, while considerably increasing the fauna, will 

 enable more exact conclusions as to the horizon of the beds to be 

 arrived at. There are few cases of specific identity between the 

 forms in the Vancouver Cretaceous, previously described, and those 

 of the Queen Charlotte Islands, the latter representing a lower stage 

 in the Cretaceous formation. The plants found in these rocks, em- 

 bi'acing numerous coniferous trees and a species of Cycad, also 

 indicate a greater age than those of Vancouver. 



The coal-bearing beds at Quatsino Sound on the west coast of 

 Vancouver Island, have also yielded a few fossils. These consist 

 chiefly of well-characterized specimens of Aucella Piochii, which 

 occurs but sparingly in the Queen Charlotte Islands, and brings the 

 rocks into close relations with the Aucella beds of the mainland of 

 British Columbia, and in Mr. Whiteaves' opinion probably indicate 

 an " Upper Neocomian " age. The rocks of the Queen Charlotte 

 Islands and Quatsino may therefore be taken together as represent- 

 ing upper and lower portions of the so-called Shasta group of 

 California, which in British Columbia can now be readily distin- 

 guished by their fossils. 



On the mainland, developed most characteristically along the 

 north-eastern border of the Coast Eange, is a massive series of 

 rocks first referred to by Mr. Selwyn, in the provisional classification 

 adopted by him in 1871, as the Jackass Mountain group, from the 

 name of the locality in which they are best displayed on the main 

 waggon-road. The age of these rocks was not known at this time, 

 but fossils have since been discovered in the locality above mentioned 

 and in several others, the most characteristic forms being Aucella 

 PiocMi and Belemnites impressus. The rocks ai'e generally hard 

 sandstones or quartzites, with occasional argillites, and very thick 

 beds of coarse conglomerate. A measured section on the Skagit 

 includes over 4400 feet, without comprising the entire thickness of 

 the formation. Behind Boston Bar, on the Eraser Eiver, the 

 formation is represented by nearly 5000 feet of rocks, while on 

 Tatlayoco Lake it probably does not fall short of 7000 feet. At the 

 last-named place these beds are found to rest on a series of felspathic 

 rocks, evidently volcanic in origin, and often more or less distinctly 

 porphyritic. On the Iltasyouco Eiver, near the 51st parallel, and 

 in similar relation to the Coast Eange, an extensive formation 

 characterized by rocks of volcanic origin, and often porphyritic, has 

 also been found. Its thickness must be very great, and has been 

 roughly estimated at one locality as 10,000 feet. It has been 

 supposed, on lithological grounds, to represent the porphyritic 

 ^ Mesozoic Fossils, vol. i. part i. 



