22 



PROCEEDINGS OE THE GEOLOGICAL SOCIETY. 



bJO 



S3 



S3 



CO 



I W 



O 



. & 



M O 



W S 



3 u 



u 



M 



o 



N 



o 



H 

 O 

 P3 

 Ph 





H 





syg 



p 3 



Upper 

 Silurian. 





Coarse 

 sandstone, 

 with a 

 band of 

 limestone 

 and cal- 

 careous 



shale. 

 ( Pen-y- 



Craig, 



S. W. of 



Meifod. ) 





Slates, with 

 a few fos- 

 sils. 



{Crest of the 

 Southern 

 Berwyns, 

 and east 

 of the 

 Crest.) 





Calcareous 

 slates, 

 with bands 

 of lime- 

 stone. 



( Glyn Cei- 

 riog.) 



Slate, and 

 band of 

 limestone. 



( Hirnant 

 river.) 





Coarse slate 

 and por- 

 phyries. 

 ( Teirw 

 River, fall- 

 ing into the 

 Ceiriog. ) 



Slate, with a 

 few trap- 

 pean bands, 

 and a band 

 of lime- 

 stone, a 

 calcareous 

 slate. 



(GlynDyffwys 

 east side of 

 Bala Lake. ) 



Coarse sand- 

 stones and 

 earthy 

 slates ; the 

 lower part 

 with the 

 fossils of the 

 Bala lime- 



• stone. 



(Tyrnwy R., 

 above Mei- 

 fod.) 



Earthy slates, 

 with arena- 

 ceous bands 

 and fossils. 



(Pont- Meibion, 

 Bwlch Llan- 

 drillo. ) 



Slate with 

 bands of 

 limestone, 

 and many 

 fossils : 

 Asaphus 

 Buchii. 



( Rhiwlas, 

 8fc.) 



Soft earthy 

 slates, 

 with are- 

 naceous 

 bands, 

 and a 

 thick 

 mass of 

 calcare- 

 ous slate. 



( Craig -y^- 

 Glyn.) 



o< 

 ■+* 



S3 

 to 



>-. 



^3 

 -u 



u 



C3 



0> 



«S 



o 



CO 



Porphyries, 

 with a 

 few bands 

 of slate. 

 ( Arenig 

 Fawr. ) 



to 



0) 



ts 



1o 



+j 

 M 



o 



o 

 CO 



Slate and 

 porphyry, 

 with crys- 

 talline 

 limestone 

 and a few 

 fossils, e.g. 

 Asaphus 

 Buchii. 



(W. of Are- 

 nig Fawr.) 



Slate and 

 porphy- 

 ries. 



(No fossils 

 yet dis- 

 covered. ) 







Chlorite 

 Slate. 



(From 

 Porth 

 Dinlleyn 

 to Bard- 

 sea Island, 

 in the 

 S.W. of 

 Carnar- 

 vonshire. 







i . j 



t i 



t ) 



West of the 

 Berwyns. 



East side of 

 the South< 

 Berwyns. 



East side of 

 the Norths 

 Berwyns. 



