24 



THE GEOLOGIST. 



flagstones ; S, the roofing slates of Kirby Julith ; 4, a se- 

 cond band of calcareous slates with lower Silurian fossils ; 

 and 5, an upper series of flags and slates which reach to the 

 neighbourhood of Ulverston. The last beds are overlaid by 

 strata of a coarse composition^ but which^ in a section con- 

 tinued to Morecambe Bay, do not show any upper fossilife- 

 rous bands. 



Ji^eland and South of Scotland. — Some sections in the 

 counties of Waterford and Kerry, are then briefly noticed. 

 They exhibit a fine sequence of lower Silurian rocks, but the 

 connection with the older non-fossiliferous slates is not 

 visible. 



Mourne Mountains — Galloivay chain, &c. — After a few 

 details on the physical features and mineral composition of 

 Downshire, Mr. Sedgwick describes the chain, extending 

 from the Mull of Galloway to St. Abb's Head. The pre- 

 vailing strike of this range, like that of the Mourne Moun- 

 tains, is about north-east by east, even in the neighbourhood 

 of protruded masses of granite. The strata consist generally 

 of a hard, fine, or coarse greywacke passing occasionally 

 into roofing slates, and destitute of fossils, except in the 

 finer schists, in which the Graptolites foliaceus has been 

 found. The strata which break out from under the carbon- 

 iferous basin of Girvan water, in Ayrshire, are next described, 

 and shown to contain many Silurian fossils. Lastly, a 

 synoptical table is given of the great groups ranging from 

 the carboniferous series to the lowest beds of the north of 

 England, the classification being as follows : — 1. The car- 

 boniferous series. 2. The old red sandstone (Devonian 

 system). 3. Silurian system. 4. The sub-Silurian, or 

 Upper Cambrian. 5. The lower Cambrian, including the 

 great groups of North Wales below the Bala limestone and 

 the older roofing slates of Cumberland. 6. The lower-Cum- 

 brian or Skiddaw slates, and containing provisionally the 

 chloritic slates of Anglesea and Caernarvonsliire. 



