112 THE ROYAL SOCIETY OF CANADA 



Brook) are gneissic and schistose rocks, which may well be much 

 older. 



(4) Evidences of diastrophism are everywhere to be met in 

 connection with the Archaean rocks of Southern New Brunswick, 

 though it is by no means easy to fix the time of such disturbances. 

 As regards the deposits (granites, syenites, etc.) to which the name 

 Laurentian has been here restricted, these are so largely of batho- 

 lithic. origin that the time of their production and the movements to 

 which they have been subjected can only be conjectured, and even 

 the accompanying gneisses may owe their appearance to similar 

 causes; but, it is certain that we have not in New Brunswick any- 

 thing in the way of a stratified formation distinct from and uncon- 

 formable to the Laurentian such as has at some places been found 

 beneath the latter in the region of Lake Superior. On the other 

 hand granitic batholiths, similar to those of the Laurentian, pene- 

 trate, in the St. John region, not only the upper or limestone division 

 of this system as first described, but also the overlying Huronian and 

 even Cambrian. They may therefore be, in part at least, of any age 

 earlier than Silurian, but are to be distinguished from the great 

 batholiths which, as stated in the sequel, were one of the most dis- 

 tinguishing features of late Devonian times. 



As regards the upper or limestone belts associated with the 

 Laurentian area, these show everywhere evidences of profound dis- 

 placement and metamorphism. They abound in folds, faults and 

 slickensides, and though containing no conglomerates, the limestones 

 of the series, which vary greatly in colour, texture and composition, 

 are sometimes so shattered as to have become, after reconsolidation, 

 a coarse breccia. No discordances, such as would mark time-inter- 

 vals or periods of erosion are found between different portions of the 

 series but the latter unquestionably rests upon Laurentian rocks 

 and is itself similarly covered by the Huronian and Cambrian sedi- 

 ments, whose lower conglomerates were in part derived therefrom. 



(6) What are the evidences of Life in connection with the Pre- 

 Cambrian rocks of New Brunswick ? The answer is still negative with 

 the possible exception of the upper or limestone group about St. John. 

 The occurrence of heavy beds of very pure limestones is in itself a 

 presumptive proof of the existence at the time of their origin of lime- 

 secreting organisms, and to this presumption force is added by the 

 fact that many of these limestones are graphitic and even contain 

 considerable beds of impure graphite. The only form, however, 

 excepting sponges, as yet met with to which an organic origin has been 

 definitely assigned is one to which Matthew has given the generic 

 name of Archœozoon. It occurs in the form of masses nodular in 



