MINERALS AND GEOLOGY OF CANADA. 441 
ments of this chert. Fossils are very abundant, but the greater num- 
ber appear to be identical with those of the overlying Corniferous 
formation. This fact, combined with the cherty character of the 
beds, renders the separation of the two groups little more than a mere 
arbitrary distinction. Amongst other forms, the followmg may be | 
enumerated as especially abundant :—Favosites Gothlandica (fig. 215), 
Zaphrentis prolifica (fig. 230), Strophomena rhomboidalis (fig. 232), 
Atrypa reticularis (fig. 240), Stricklandia elongata (fig. 236), Penta- 
merus aratus (fig. 235), and Calymene Blumenbachii (fig. 209). 
This formation, which is somewhat extensively developed in the 
State of New York, enters Western Canada in Bertie township (about 
opposite to Buffalo) and appears to extend as a thin band along the 
southern edge of the Eurypterus or Onondaga deposits, at least as 
far as the County of Norfolk; but the only known exposures occur 
at places in the townships of Bertie, Dunn, North Cayuga, Oneida, 
and Windham. From the exposure in North Cayuga, a little north 
of the Talbot road, good millstones have been obtained.* 
The Oriskany formation is probably represented in Eastern Canada, 
according to Sir William Logan, by some of the sandstones of Little 
Gaspé and that district. A small seam of coal, under two inches in 
thickness, occurs in these beds, together with numerous carbonized 
plants. The latter have been described and figured by Dr. Dawson 
in the Canadian Naturalist, vols. V. and VI. 
The Corniferous Formation.—This group of strata includes the 
“Onondaga limestone” and the ‘‘ Corniferous limestone”’ of the New 
York geologists. Its name is derived from the occurrence of nodular 
masses and layers of chert or hornstone in many of its beds. It is 
made up essentially of limestones, generally free from magnesia, but 
often highly bituminous, combined with layers of chert, and with a 
few beds of calcareous sandstone and an occasional band of bitumi- 
nous shale. The total thickness of the formation, with us, is apparently 
under 200 feet, but this is somewhat doubtful. The limestones are 
exceedingly fossiliferous ; and in places (more especially towards the 
base of the formation) they abound in fragments of crinoids and other 
organic remains in a silicified condition. The fossils, indeed, are 
mostly, though not entirely, in this condition throughout the group. 
* These are manufactured by Mr. DeCew, Provincial Land Surveyor, of DeCewsville, near 
Cayuga, in Haldimaud County: from whom, also, interesting suites of fossils, belonging to 
the formations of that district, may be procured. 
Vou. VIIL.: 26 
