NEW BRUNSWICK. 369 



1879, placed this point beyond question, tbey having been then found by me to 

 occupy irreguhir troughs in the okler Pre-Siluiiun rocks, resting sonietiiues 

 upon one and sometimes upon another of the subdivisions of the latter, crossing 

 their strike obliquely, and having at their base coarse conglomerates made up 

 of the waste of the underlying formations. The latter being thus unquestion- 

 ably of Pre-Siluriau age, it is equally obvious that in their vast thickness, in 

 the markedly different conditions under which their several divisions were 

 accumulated, and finally in the further unconformability indicated betAveen 

 these divisions, they represent a vast interval of time, and are at least as old as 

 the Huronian and portions of the Laurentian system, which in all their physi- 

 cal characters they so nearly resemble. No more marked coordination of dis- 

 tant formations could be desired than is here furnished between the great mass 

 of coarse gneisses at the base of the series, associated with finer gneisses, quart- 

 zites, graphitic and serpentinous limestones and dolomites (the probable equiv- 

 alents of the Hastings' series of Mr. Vennor), and capped by the great volcanic 

 series of the Huronian, with its petrosilicious and felsitic strata, ash-rocks and 

 agglomerates, the whole unconformably traversed by bands of the lowest Cam- 

 bro-Silurian, and the similar succession observed about Lake Huron and else- 

 where It should be added in this connection that in the rocks here 



assigned to the Huronian, there are as a whole two well-marked divisions, the 

 lower (or Coldbrook group) consisting almost entirely of fine grained felsitic 

 strata, with diorites, amygdaloids and porphyries, and the upper (or Coastal 

 group) of schistose rocks, often talcoid or nacreous, with conglomerates and 

 limestones and holding ores of copper, and that between the two there is not 

 unfrequently evidence of at least a partial unconformability, but in general 

 the relations to each other are much more intimate than are their relations 

 either to the underlying Laurentian, or to the Primordial strata which overlie 

 them." (/. c, pp. 416, 417.) 



In this paper the Kingston was separated by Prof. Bailey into two 

 groups : one of these was placed in the Huronian, and the other in the 

 Lower Silurian. This author further states, that the Upper Silurian 



" age can now be definitely assigned to the very remarkable group of rocks sur- 

 rounding Passamaquoddy Bay, and which include the peculiar orthophyres or 

 felspar-porphyries of Eastport and Pembroke, Me., these latter having been 

 found to rest dii-ectly and almost horizontally upon a series of fossiliferous 

 sandstones, identical with those which at the last-named locality have been 

 long known to contain a rich Upper Silurian fauna. Another instance of the 

 difiiculty of distinguishing the rocks of this most variable formation is to be 

 found in the occurrence, first observed by Mr. Matthew, of corals and other 

 Silurian organic remains on the Long Reach of the St. John River, in amygda- 

 loidal ash-rocks, which are undistinguishable lithologically from those of the 

 Huronian formation, and which, like those of Passamaquoddy Bay, had pre- 

 viously been referred to this horizon." (I. c, p. 421.) 

 VOL. vn. — NO. 11. 24 



