142 Silurian and Devonian Rocks 



of fossils. The iron ore is not seen, but tliere are highly fossil- 

 iferous slates and coarse arenaceous limestone, and a bed of gray 

 sandstone with numerous indistinct impressions apparently of 

 plants. In addition to several of the fossils found at Nictaux, 

 these beds afford Tentaculites^ an Atrypa, apparently identical 

 with an undescribed species very characteristic of the Devonian 

 sandstones of Gaspe, and a coral which Mr. Billings identifies 

 with the Pleurodictyum p'ohlematicum^ Goldfuss, a form which 

 occurs in the Lower Devonian in England, and on the continent 

 of Europe. 



Westward of Bear Eiver, rocks resembling in mineral charac- 

 ter those previously described, extend with similar strike, but in 

 an altered condition, and in so far as T have been able to ascertain, 

 destitute of fossils, quite to the western extremity of the peninsula, 

 where they turn more to the southward, and are as I suppose, 

 repeated by a sharp synclinal fold, after which they are succeeded 

 by the Atlantic coast series, consisting of quartzite and clay 

 slate, with chlorite and hornblende slates at Yarmouth and its 

 vicinity, and further to the S. E. of mica slate and gneiss. 



General Remarks. 



The above facts show that we can recognise among the partially 

 metamorphosed sub-carboniferous rocks of Nova Scotia, forma- 

 tions ranging from the Middle Silurian to the Lower Devonian 

 inclusive ; but of a more argillaceous and less calcareous charac- 

 ter than the series occupying this position in the mainland of 

 America. The principal masses of plutonic rock associated with 

 these beds, and especially the granite, are of newer Devonian 

 date ; but there is evidence of igneous eruptions as far back as 

 the beginning of the Upper Silurian, and of the continuance or 

 recurrence of such action as late as the carboniferous period. In 

 and near the non-calcareous Lower Silurian series, granite prevails, 

 almost to the entire exclusion of other plutonic rocks. At a 

 greater distance from these, the plutonic rocks penetrating the 

 Upper Silurian and Devonian series, though apparently of nearly 

 the same age with the granite, are principally syenite and green- 

 stone. 



With respect to the general arrangement of the formations, 

 though I cannot venture to speak with confidence on this point, 

 with reference to a district so much disturbed, and which 1 have 

 been able only very imperfectly to explore, I may suggest, as at 



