5 b. „Mjøsen limestone". Compact 



li. & sandy li. 

 5 a. Highest i^hastnops zone. Shale 



& sandy li. 



5 b. Sandstone & sandy li 



very poor in fossils. 

 5 a. „Gastropod li." 



5 b. Sandy li. with Meristella 



crassa. 

 5 a. „Gastropod li". 



Li. with Cyclocrinits, Pled, sericea. 



4 d. Isotelus li. 



4 d. Isotelus 



Shale with Cyclocrimts, Pled. 

 sericea. 



4 c. TriHucletis shak 



4 c. 



Trinudeus shale. 

 Trinitdeits li. 



4- \ 



Shale and sandy li. with Coelo- 



spliccridittitt. 

 Unlossiliferous shale & sandy li. 



Shale with cephalopods and 

 gastropods. I 



Nodular li. with Alliens anna' \ 

 dillo. 



Shale with Ogygia dilatata. 



4 a — b.- 



3 c ;■•. 

 3 c/?. 

 3 ca 

 3 b. 

 3 a- 



Li. 



Unfossiliferous shale 

 and sandy li. 



4 b 0. Upp Cliasinops li. 



4 b y, Upp Chasmops shale. 



4 b ^. Low. Chasmops li. 



4 b a. Low. Chasmops shale. 



Shale with cephalopods 

 and gastropods. 



Shale with Ogygia 

 dilatata. 



3C/- 



3 c a. 

 3 b. 

 sa. 



4 a ß. Li. with Ampyx. 

 4 a a. Shale with Ogygia 

 dilatata. 



3 c 7. 

 3^ß- 

 3 ca. 

 3 b. 

 3 a. 



Table II. Principal Divisions of the Siluric in 



South Wales. 



Ringerike. 



Downtonian. 



Ludlow shales 

 and sandstones. 



Wenlock shales 

 and sandstones. 



Downtonian. 



Ludlow 

 (9). 



Wenlock 

 (8). 



Red sandstones and sandy shales. In a zone near the 

 base with eurypterids, phyllocarids and fishes. 



9 g. Zone of Leperditia norvegica Kiær. Shale & li. 



9 f. Favosites li. 



9 e. Chonetes li. (Li. & shale). 



9d. Zone ot Spinfer elevatus etc. Nodular li. & shale. 



9 c. Upp. zone of Leperditia phaseolns. Alt. shale & li. 



9 b. Low. zone of Leperditia phascohts. Alt. li & shale. 



9 a. Zone of Atrypina angelini Nodular li. 



8 d. Dark li. with Leperditia baltica. 



8 c. Zone of Rhynchonetla ciineata („Wenlock li"). 



8 b. Zone of Chonetes sp and Leperditia hisingeri. Sandy li 



8 a. Zone of Cyrtia exporreda. Shale & layers of sandy li. 



Upper 



Upper Llandovery.' I Llandovery , 

 (7)- 



T cy. Upp. Crotalocrinns shale. 



7 c /Î. Zone of Stricklandiiiia lirata (Upp. Coral li.). 



7 c«. Low. Crotalocri)ius shale. 



7 b^. Low Coral li. 



7 b a. Pentameriis oblongits li. 



7 a. PentameriiS boreatis li. 



Lower 



Lower Llandovery. Llandowery 

 (6). 



6 c. Zone of Rhynchonella jo-plicata. Alt. sandy li. & shale. 

 6 b Zone of Rhynchonella IVeaveri. — » — 



6 a. Zone of Lcptocoelia hemisphaerica. — » — 



