ON THE GEOLOGY OF ST. JOHN. 253 



point where they are crossed by the section they present the fol- 

 lowing succession : 



1st. Red clay slate, and grit, and coarse reddish micaceous slate, 



resting upon the Dadoxylon sandstone. 

 2nd. A thick mass of granulite and imperfectly formed granite, 



with beds of trap-ash. 

 3rd. Grey micaceous slate. 

 4th. Reddish sandstone and grit, overlaid by coarse conglomerate 



holding beds of hematite. 

 5th. Dark grey micaceous slate, and basalt (stratified ?). 



A short distance to the eastward, the quasi-granite passes into 

 schist abounding with volcanic ash beds, and overlaid by similar 

 strata containing several large beds of iron one. 



Further east in the same metamorphic belt are a number of 

 thick belts of impure limestone much altered, and hard clay slate 

 with copper pyrites. The highest beds exposed at Black River 

 are red and green clay slates, beds of trap-ash and basalt, resem- 

 bling the volcanic sediments of the Bloomsbury group. The po- 

 sition of these metamorphic beds will be discussed further on. 



Mispeck Group. — Filling the centre of the basin of Devonian 

 rocks intervening between Little River and Mispeck River, and 

 having a breadth of about two miles, is a group of sediments in 

 which no organic remains have been found, and which there is 

 reason to suppose should be separated from the fossiliferous strata 

 below, although resembling the latter in appearance and equally 

 metamorphosed. West and north of Mount Prospect where the 

 cordaite shales disappear beneath the stratified gravel which 

 covers the top of that hill, the dip of the beds at the base of this 

 group rapidly diminishes from 30° to 15°, and the strike at the 

 same horizon varies 10°. The lowest member is a coarse reddish 

 conglomerate having a red slaty paste filled with large subangu- 

 lar fragments of a grey altered rock, like the lower slate of the 

 Coldbrook group. It also contains fragments of reddish sand- 

 stone and a few pieces of impure slaty limestone. The conglo- 

 merate is overlaid by thick beds of purple clay slate, which by the 

 accession of coarser materials becomes a slaty sandstone and grit 

 filled with white particles. The highest member on the line of 

 section is a slaty conglomerate holding fragments of slate and 

 sandstone. The strata of this group are much thicker on the 

 north than on the south side of the basin. An isolated deposit 



