6 Rev. W. D. Conybeare on a Geological Map of [Jan. 



moreland and Cumberland is the next which presents itself in 

 advancing to the south. Granite is here of confined and limited 

 occurrence; various rocks of the greenstone family and transi- 

 tion slate predominate ; transition limestone occurs associated 

 with the slate. 



The central chain of the Isle of Man lying midway between 

 this group and the Irish coast is also composed principally of 

 transition slate. 



The mountains of North Wales, including the northern half of 

 South Wales, are like those of Cumberland, composed of transi- 

 tion slate, and many varieties of greenstone rocks.* 



The Isle of Anglesea presents, in addition to these, chlorite 

 slate, serpentine, quartz rock, and granite. The granite is 

 described by Mr. Henslow, who has given a most elaborate and 

 interesting account of this island as presenting the strongest 

 evidence of igneous origin ; and having be^n formed, in one 

 instance at least, by the fusion of old red sandstone in situ. 



A zone of transition limestone skirts the east of the Welch 

 chains in their course through Shropshire. 



On the south-east of the Welch chains lies the detached 

 group of the Malvern hills, consisting of a protruding range of 

 sienitic rocks flanked on the west by transition limestone, dip- 

 ping rapidly in that direction, and appearing, according to Mr. 

 Horner, as if elevated by the protrusion of the sienitic mass on 

 which they repose. 



In the centre of England another group of sienitic and green- 

 stone rocks starts up in the midst of the secondary deposits con- 

 stituting the ranges and tors of Charnwood Forest, in Leicester- 

 shire. The coal measures, &c. in approaching this group, are 

 much disturbed and elevated. Some slate rocks here accompany 

 the sienite. 



The coasts of Ireland opposite to the Welch, to which we may 

 next proceed, present in the Wicklow mountains a fuller develop- 

 ment of the usual primitive series, mica slate, gneiss, Sec. than the 

 chains last described. The granite here forms lower mountains 

 principally on the western side of the chain, and extends into the 

 plains at their base, mica slate constituting the loftiest summits. 

 Transition slate, greenstone, and quartz rock, occur on the east- 

 ern border. This chain prolongs itself to the south-west through 

 Wexford, Cork, and Kerry, where it skirts the lakes of'Killarney, 

 but in the two latter counties, transition rocks almost exclusively 

 occupy it. Through its whole extent it forms a zone running 

 parallel to the south-eastern and southern coast of Ireland ; and 

 it is a remarkable circumstance, that many rivers rising beyond 



* I now use the term only as a general description of an extended class of rocks in 

 Cader Idris, the Arrans, &c. and do not enter into the more minute details lately pub. 

 Jjshed in the Annals concerning the Snowdonian range. 



