RICHMONDIAN SERIES 695 



a very similar thickness. These strata are essentially thin-bedded inter- 

 stratified limestone and shales with a few thick zones of pure limestone 

 and shale and rarely horizons of sandstone. The zonal classification here 

 adopted is in the main that of Eichardson, first published in 1857 and 

 later slightly changed by Logan.^^ The "Hudson Eiver group'' of Bil- 

 lings^* and the basal division of his "Anticosti group'' are here referred 

 to the Eichmondian, and for the main part of his second group the series 

 term Niagara will be used. 



The Eichmondian series of Anticosti is clearly divisible into the three 

 divisions as defined by Eichardson. His Division A is best seen at the 

 western end of the island at English Head, and these strata will here be 

 referred to the English Head formation. Division B is well exposed on 

 the north side at Charleton Point and Observation Cliff. The latter 

 place is diSicult of access, but at the former locality may be collected an 

 abundance of fossils, and for this reason these strata will be named the 

 Cliarleton formation. Eichardson's Division C must on faunal grounds 

 be divided, and this designation will be retained only for the lower 180 

 feet, the remainder of his C zones, C12-C14, which have a thickness of 139 

 feet, being referred to his Division D. These lower beds of C are best 

 studied about Ellis Bay, and they will be here named the Ellis Bay for- 

 mation, the higher beds being referred to the Becsie Eiver formation. 



English Head formation {Richardson's Division A). — The thickness 

 of this formation is about 229 feet, and is divided by Eichardson into six 

 zones, here numbered A^ to Ag. 



The lowest zone of this division, or A^, is thought to rest on the black 

 Macastey shale. The actual contact can not be seen, but around Macastey 

 Bay large pieces of the black shale are thrown on the shore, presumably 

 by the storms, torn undoubtedly from the shallow depths beyond the 

 reefs. How much of A^ is concealed by the sea is not determinable. The 

 lowest strata of this zone are found on the reef at English Head, but at 

 that point flakes of the black shale are rarely seen. The shale occurs in 

 greatest abundance in the bay east of Macastey Mountain, where its 

 presence is doubtless explained by increased wave action on perhaps an 

 elevated portion of the sea bottom. In view of these facts, the writers 

 prefer not to make estimates of the thickness that may exist down to the 

 black shale contact. Division A consists of gray to light greenish thin- 

 bedded limestone with thin partings of green and gray shales. At many 

 levels zones of intraformational conglomerates occur locally, attaining to 



" Richardson : Report of Progress, Geological Survey of Canada, 1857. pp. 206-235. 



Logan : Geology of Canada, 1863, pp. 221-223, 298-304. 

 " Billings : Catalogues of the Silurian Fossils of the Island of Anticosti, Geological 

 Survey of Canada, 1866, pp. 1-93. 



