306 WALCOTT 



Middle Cambrian^ dowtzward. — • 



Feet. 



la. Dark, argillaceous shales, with fragments of Paradoxides 

 in the upper portion. At 45 feet down the Paradoxides 

 are abundant ; also Acrothele^ Obolus (L,.) ferrugineus^ 

 Ptychoparia^ etc. At no feet down a 4-inch band of 

 pinkish limestone carrying fragments of trilobites occurs. 

 A roll in the strata comes in at this point and continues 

 for a considerable distance along the shore. It starts 

 betwee'^i the two east wharves at Broad Cove, and ex- 

 tends some distance east of the eastern point of Broad 

 Cove no 



lb. Below the limestone greenish shale extends downward to a 



layer of reddish argillaceous shale 20 feet in thickness... 80 

 No recognizable fossils were found in this bed. 



ic. Pinkish nodular limestone in several layers, interbedded in 



reddish shale 4 



Fossils: Paradoxides (undet.), Ptychoparia. 



id. Reddish-purple argillaceous shales with interbedded 



greenish-colored bands 1 35 



This band of shales corresponds stratigraphically to the 

 Protolenus zone of the Hanford Brook section of New 

 Brunswick. A basalt dike cuts through the shales a few 

 feet above their base. On the weathered surface it has 

 the appearance of a massive sandstone. It is 3 feet 4 

 inches in thickness, is vertical, and the dip of its cleavage 

 planes is almost coincident with the dip of the shales. 



le. Nodular limestones. A pinkish layer 4 inches thick con- 

 tains at base numerous fragments of trilobites and ap- 

 pears to be made up of a conglomerate formed of frag- 

 ments of pinkish-colored limestone and purple shale, 

 and dark iron- or manganese-stained nodules resembling 

 a Stromatoporoid-like growth, and a few small quartz 

 pebbles. 



The entire stratum is as follows : 



Inches. 



Dark, nodular limestone 25 



Purplish-colored shale 2 



Pinkish limestone 2 



Brick- red shale 3 



Pinkish conglomerate } limestone...... 4 3 



At the point of exposure on the shore this band is faulted 



down 15 feet to the west. It is exposed near the top of 



the bank on the eastern side of the fault, where its dip is 



lower than on the western side. 

 The stratum le is taken as the base of the Middle Cambrian 



(Paradoxidian). It is the horizon indicated by Mr. 



Matthew in his diagrammatic section as the base of the 



