570 THE UPPER SILURIAN. 



* Atrypa reticularis. 



* Crania (?) Acadiensis. 



Athyris [Meristella) didyma, a characteristic European Upper 



Silurian shell. 

 Lingida. 



* Megamhonia striata. 

 Megambonia (?) n. s. 

 Clidophorus (?) n. s. 

 Pterinea or Megambonia. 

 Orthonata or Nuculites (?) u. s. 



* Bucania trilobita, Hall. 

 Murchisonia, two species. 

 Platyceras. 



* Orthoceras punctostriatum, Hall. Some specimens found at 



East River, with the external markings of this species, are 



as much as two inches in diameter. 

 Orthoceras (?) n. s. 

 Cyrtoceras (?) n. s. 



* Cormdites flexuosa, and probably another species. 

 Beyrichia^ two or more species. 



* Calymene Blumenbachii. 

 Serpulites. 



* Stenopora allied to S. fibrosa. 



Cobequid Mountains. — At the eastern end of this chain, in Earlton 

 and New Annan, though the rocks are generally in a highly meta- 

 morphosed condition, fossils are found in a few places ; and in so 

 far as I have been able to determine from very small suites of speci- 

 mens, are those of the Arisaig series. From the apparent continuity 

 of strike along this long salient line of outcrop, it seems probable that 

 these fossils indicate the true age of the greater part of the sedi- 

 mentary rocks of the Cobequid Hills ; a conclusion confirmed by 

 their similarity in mineral character to the altered equivalents of 

 the Arisaig and East River series as seen elsewhere. There are, 

 however, some indications of beds of Devonian age, along the flanks 

 of these hills, especially at their eastern end. The arrangement 

 of the beds and their mineral contents, in the central part of the 

 chain, will be found noticed in my paper of 1849, already referred 

 to. They are not known to contain beds of iron ore ; but have 

 enormous vein-like deposits of spathic and specular iron associated 

 with the carbonates of lime and magnesia, and running with the strike 

 of the beds. These will be described in the section relating to 

 useful minerals. 



