MIDDLE AND UPPER ORDOVICIAN. 207 



li 19. CABLETON AND YOBK COUNTIES, NEW BRTTNSWICK. 



The slate belt that extends from the boundary of Maine northeastward to 

 Chaleur Bay is naapped as Cambrian and Ordovician, without distinction of the 

 middle and later Ordovician, which, however, occur there. The lithology of the belt, 

 according to Bailey,*^ is monotonous, yet the rocks range in age from Cambrian to 

 upper Silurian. The sequence is not complete, the base of the Silurian being marked 

 by a distinct basal conglomerate containing the older Paleozoic rocks as cobbles, 

 but it is not known how much of Ordovician time is represented by the unconformity. 

 Bailey *" names the few localities at which the fossils have been found and Ami^^ 

 describes those from Tete a Gauche River which are of Ordovician age. The latter 

 describes " Fossils from the black carbonaceous and graptolitic shales from near the 

 railway bridge on the Tete a Gauche River, near Bathurst, Gloucester County, New 

 Brunswick," and names them as follows: 



Diplograptus foliaceus Muicliison. 

 Diplograptus truncatua Lapworth. 

 ?Laaiograptu8 sp. indt. 

 Climacograptus bicomis Hall. 

 Cryptograptus tricomis Camithers. 

 Dicellograptus sextans Hall. 

 Dicellograptus anceps Nicholson. 

 Orthograptus quadrimucronatus Hall. 

 ?Didymograptus superstes Hall. 

 Leptobolus sp. 



The above assemblage of forms suggests at once an Ordovician fauna belonging to one of 

 those zones of graptolites occurring along the St. Lawrence and the Hudson rivers. Similar 

 forms from rocks of presumably the same age have also been found in Penobscot County, Maine." 



These black and at times pyritiferous shales appear to be synchronous or homotaxial with 

 the shales of Normans Kill, near Albany, N. Y., of the city of Quebec, of the north shore of the 

 Island of Orleans, of the Marsouin River, and of numerous other localities in the Gaspe Penin- 

 sula. They find their equivalent in Europe in the Llandeilo rocks of Wales, the Moff att shales 

 of Scotland, and the County Down shales of Ireland. 



M 11. BBAVEBFOOT BANGE, CANADIAN BOCKY MOUNTAINS. 



Graptolitic shales are described by McConnelP^""^ as occurring between the 

 Castle Mountain group (Cambrian and Ordovician) and the " Halysites beds, " into 

 both of which they appear to graduate in sections along the Canadian Pacific Rail- 

 way, east of Columbia River. They are hard black fissile slates, 1,500 feet thick, 

 which in some sections alternate with thin beds of limestone and here and there, 

 near the top, with quartzites and dolomites. Lapworth, reporting on the grapto- 

 lites, identified Didymograptus sp. nov., allied to Didymograptus euodus Lapworth, 

 Glossograptus ciliatus Emmons, G. spinulosus Hall sp., Cryptograptus tricornis Carr 

 sp. = C. marcidus Hall sp., Diplograptus angustifolius Hall, D. rugosus Emmons, 

 Climatograptus coelatus Lapworth, and doubtful species of Phyllograptus or Lasio- 

 graptus. These forms are referred to " the age of the Utica slate or at any rate to 

 the Trenton-Utica fauna of the United States and Canada. The association of forms 

 is just such as occurs in the Llandeilo (lower and middle) of Britain, and some forms 

 are common to both sides of the Atlantic." 



a Am. Jour. Sci., 3d ser., vol. 22, 1881, p. 434; vol. 40, 1890, p. 153. 



