NOVA SCOTIA. 567 



to devote sufficient time to this object to attempt to trace the beds in 

 their succession or continuation inland. 



Dr Honeyman has addressed himself with some success to the work 

 of tracing the relations and continuation of the beds exposed in the 

 Arisaig section, and has published an interesting paper on the subject 

 in the Journal of the Geological Society (1864). In this paper he 

 divides the whole series seen at Arisaig into five sub-sections, noted 

 respectively in ascending order as A, B, B', C, D. He distinguishes 

 the groups A and B from my Lower Arisaig series, which he regards- 

 as equivalent to his groups B' and C, while D is the equivalent of 

 my Upper Arisaig series. 



Group A, of Dr Honeyman's paper, includes the altered jaspideous 

 shales seen near Arisaig Pier, and the gray argillaceous and arenaceous 

 shales of Doctor's Brook. Dr Honeyman mentions, as occurring in 

 them, species of Orthoceras, Murchisnnia^ Strophomena^ Orthis, Rhyn- 

 chojiella, Calymene^ Cornulites^ Tentaculites^ and Petrala (?), and, on 

 the authority of Mr Salter, regards them as equivalents of the English 

 Mayhill sandstone, a member of the Upper Llandovery series. Their 

 thickness is estimated at 200 feet. 



Groups B and B' include principally dark and ferruginous shales. 

 One of the most characteristic fossils of which is GraptoUthus Clinto- 

 nensis. They contain also Tentaculites, joints of crinoids, Strophomena 

 depressa, and other fossils ; and Dr Honeyman has added in his paper 

 two species of Grammysia, G. triangulata^ and G. cingulata, and 

 several other fossils not determined as to species. This group is 

 regarded by Dr Honeynaan and Mr Salter as equivalent to the Lower 

 Ludlow of England, which is above the horizon of the American 

 Clk^ton and Niagara. 



Group C, which is also characterized by fossils in the main Clinton 

 in character, is regarded by Dr Honeyman and IMr Salter as the 

 equivalent of the subordinate group known in England as the Ay- 

 mestry limestone. The beds of this group are harder than those of 

 the last and more calcareous ; and in addition to the fossils mentioned 

 above as characteristic of the Lower Arisaig scries, Dr Honeyman 

 mentions Rhynchoyiella Saffordi^ Spirifer rugaecosta, and some other 

 fossils previously regarded by me as characteristic of the upper series, 

 and which indicate that this group includes the transition from the 

 lower to the upper member. 



Group D, of Dr Honeyman's paper, is equivalent to my Upper 

 Arisaig series, and contains a great number of fossils, some of which 

 are of Lower Helderberg or Upper Ludlow types, and so strikingly 

 resemble those figured by Sir R. Murchison in his " Siluria," as char- 



