]48 Geological Society: Prof. Sedgwick on the 



lower division is Lower Silurian, and that the upper division ends at 

 the very top of the Silurian system, and includes beds which have 

 been classed with the old red sandstone — an arrangement which is 

 natural in South Wales, but is not sanctioned by the Westmoreland 

 sections. 



The want of good mineral or fossil groups to distinguish the mid- 

 dle portion of the section, makes the real difficulty of representing the 

 divisions on a map. 



The author then briefly noticed two other sections ; one from the 

 Shap granite, through the fossiliferous slates, &c, to Howgill Fells. 

 These, in their range southwards through Middleton Fells, &c, are 

 placed in the upper division, though not in the highest part of it, 

 which is described above. They contain very few fossils, but those 

 which have been found are of the Upper Silurian system. 



Lastly, the author briefly mentioned the phenomena of another 

 ascending transverse section from the western end of the calcareous 

 slates, as follows : — 



(1.) Calcareous slates (Caradoc) of Milium in Cumberland. 



(2.) Quartzose flagstone, coarse pyritous shale and slate, &c. 



(3.) Roofing slates of Kirkby Jreleth. 



(4 .) Second band of calcareous slates, also with Lower Silurian fossils . 



(5.) Upper series of flags and roofing-slate extending to the neigh- 

 bourhood of Ulverston ; and in turn overlaid by coarser beds, which, 

 however, in a section continued to Morecambe Bay, did not show 

 any of the upper fossil bands. 



Ireland and South of Scotland. — The author then shortly notices 

 some sections in the counties of Waterford and Kerry (to which he 

 was conducted by Mr. Griffith). They exhibit a fine sequence of 

 true Lower Silurian rocks, but do not show their relations (at least 

 in any section seen by the author) to the older non-fossiliferous slates 

 of the south of Ireland. Hence, though excellent examples of a group 

 of upper fossiliferous slates, they do not offer any help as to the 

 number and order of the natural groups into which the great in- 

 fra-carboniferous series may be conveniently divided. He then points 

 out that the grouping of the older strata in the south of Ireland, now 

 given by Mr. Griffith, is not only sanctioned by the sections, but 

 gets rid of a great supposed anomaly, — viz. the re-appearance of the 

 carboniferous fossils at different levels on a general descending sec- 

 tion of the older rocks of Ireland. 



The author then briefly notices the fossils in the true Silurian rocks 

 in the north of Ireland, in progress of publication by Captain Port- 

 lock. They form an admirable series, but the sections do not appear 

 to connect the group of rocks containing them with the older forma- 

 tions, so as to lend much help in their subdivisions or grouping. 



Mourne mountains, Galloway chain, SfC. — After a few details re- 

 specting the mineral structure, strike, altered rocks, granite veins, 

 &c, of Downshire, the author proceeds to notice the Galloway chain 

 (which extends from the Mull of Galloway to St. Abb's Head). Its 

 prevailing strike, like that of the Mourne mountains, is about N.E. 

 by E. ; and this is sometimes persistent, even in the neighbourhood 



