Srcrron IV., 1895. [258 ] _ Trays. RS. C. 
XIII.— Traces of the Ordovician System on the Atlantic Coast. 
By G. F. Marruew, D.Sc. 
x 3 
(Read May 25, 1893.) 
In the early history of the geology of the maritime provinces of 
Canada the distinction between the different grand divisions of the Palæo- 
zoic rocks was not very clearly drawn. 
This arose partly from the fact that the earlier geologists drew no 
distinction between the Cambrian and Lower Silurian (Ordovician) or 
between this and the Upper Silurian ; and partly because all the Palæo- 
zoic deposits, except the Carboniferous, had been greatly disturbed and 
folded in almost every part of this region, Owing to these disturbances 
there exists here a confused complex of the older and middle Paleozoic 
that is difficult to unravel. 
But the want of sharpness and accuracy in the several divisions of 
the Paleozoic rocks has also arisen from the scarceness of well preserved 
fossils, whereby these divisions and their several parts could be distin- 
guished from each other. 
Latterly, and by slow degrees, group after group of the older Paleo- 
zoic rocks have been recognized, and the earlier classification improved. 
First, Dr. Abraham Gesner distinguished the Silurian (Upper) of the north- 
ern part of New Brunswick ; then Sir J. W. Dawson claimed the existence of 
Silurian (Upper) and Devonian in the valleys of Cornwallis and Annapolis 
in Nova Scotia; at a later date Dr. D. Honeyman collected the Silurian 
(Upper) fossils of Arisaig, N.S., which were described by Jas. Hall, and 
the Cambrian fossils of Mira River, C.B., recognized as such by J. W. 
Salter. At a later date the officers of the Geological Survey discovered 
Silurian fossils at Winthrop Station, N.S. 
Meanwhile the Cambrian rocks of St. John were determined as such 
by the discovery of a distinctive marine fauna ; and the Devonian age of 
plant-remains of Lancaster was asserted by Sir Wm. Dawson. Sub- 
sequently the officers of the Geological Survey distinguished by their 
fossils the rocks of various Silurian (Upper) areas in New Brunswick. 
But among all these no trace of an Ordovician fauna had been 
obtained. The first step in this direction was the discovery (1880) of 
fossils of this age in certain quartzites and siliceous slates on the Beca- 
guimic River in the northwestern part of New Brunswick. These were 
a species of Harpes, a Leptobolus, another Brachiopod resembling Leptella 
(?) decipiens, Bill.,! and other fossils, undetermined. To the southwest of 

1 Rep. Prog. Geol. Surv. Can., 1885, Rep. G, p. 25. 
