1865.] GEOLOGY OF NEW BRUNSWICK. 233 



of silicious slates which appear to underlie unconformably a series 

 of Upper Silurian argilites, green, red, and blue-black, and hold- 

 ing Favosites GotMandica. The strike of these silicious slates 

 would carry them to the north of Nictau Lake, and this line pro- 

 longed in a southwesterly direction is supposed to form a rude but 

 continuous curve, which may provisionally represent the northern 

 boundary of the Quebec Group, which has been brought to the 

 surface simultaneously with the granite axis of Devonian age 

 described in Chapter II. 



" The continuation of this boundary takes a southerly course and 

 is supposed to cross the Shiktehawk about 3 J miles from its mouth, 

 where a conglomerate occurs, described in Chapter VI. It crosses 

 the Saint John below Presquile, and taking a southwesterly course 

 it enters the State of Maine near the forks of the Meduxnekeas:, 

 pursuing its course towards the Atlantic Ocean on the north flank 

 of the granitic axis, where it is represented on Mr. C. H. Hitch- 

 cock's Map of Maine as a belt of mica schist. On the south-east 

 side of this axis the Quebec Group is again brought to the surface, 

 its eastern boundary being in great measure covered up by the 

 Bonaventure formation or base of the carboniferous series, which 

 in many places reposes upon it horizontally or nearly so. Until 

 further investigations establish the contrary, all the sedimentary 

 rocks, with the exception of the carboniferous, north of the granitic 

 axis, which comes in from the State of Maine at Saint Stephens, 

 and proceeds in an easterly direction through Queen's County to 

 and beyond the Saint John, may be considered as belonging to this 

 group, although it is not improbable that there is a narrow belt of 

 middle silurian rocks, on the north-east flank of the carboniferous 

 series a few miles due west of Fredericton. The rocks on the north 

 side of this last-named axis, described by Hitchcock as mica 

 schist, in its prolongation through Maine to the Atlantic Ocean, 

 most probably belong to the Quebec Group. 



" The breadth of this group of rocks measured at right angles 

 to the strike within the limits of the boundaries just described, will 

 be approximately as follows, after deducting the granite axis : 



1. Five miles from Bath urst, .... .... 20 miles. 



2. From Ramsay's Brook, southeasterly, 36 " 



3. From near the Nictau " 44 " 



4. From the Tobique, " 43 " 



5. From the Maduxnekeag, " 38 " 



6. On the New Brunswick and Canada R. R., .... 25 " 



