EXPLANATION OF THE PLATES. 



Fig. 6. Zannone seen from the east. 



Fig. 7. South-east view of Ventotiene and San Stefano. 



PLATES XXVL & XXVII. 



Illustrate Mr. Yates's paper on the Structure of the Border Country of Salop and 

 North Wales ; and of some detached Groups of Transition Rocks in the Mid. 

 land Counties. 



Plate XXVI 



Fig. 1. Map of part of the county of Warwick, &c. 



Fig. 2. Section illustrative of the same. 



Fig. 3. East and west section of the Wren's Nest. 



Plate XXVII 



Figs. 1 & 2. Impressions of plants, (fuci ?) from the slate-clay at Colmore's Farm, 

 Bromsgrove Lickie. 



Fig. 3. Beds of greenstone, breaking through the grauwacke at Griff Hollow, War- 

 wickshire. 



Fig. 4. Strata of quartz-rock, Bromsgrove Lickey. — A, B, highly ferruginous and 

 micaceous shale. 



PLATES XXVIII. & XXIX. 



Illustrate Mr. Aikin's paper on the Geological Structure of Cader Idris. 



Plate XXVIII. 



The map which occupies the greater part of this Plate represents the principal 

 features of Cader Idris and the adjacent country, copied by permission from 

 one of the Ordnance surveys. 



The winding crest of the mountain is seen stretching eastward from Bar- 

 mouth Bay to the deep transverse valley of Tal y Llyn, which runs N. E. and 

 S.W., and is the boundary of Cader Idris on that side. On the North is seen the 

 broken ground extending to the Mawddach and its accompanying marshes, and 

 consisting chiefly of trap rocks intermingled more or less with slate. From 

 Mynydd pen y Caed, a little to the South of the summit of Cader Idris, begins the 

 line of section described in Mr. Aikin's paper, which terminates North of Dal- 

 gelle, a little beyond the margin of the map. — An elevation of this section is 

 represented in outline at the bottom of the plate. 



