LIFE-ZONES IN THE BRITISH CARBONIFEROUS ROCKS. 



219 



Thickness 



15 



Locality- 



is 



(Esti- 35 

 mated) 



Thicknesg 



6 

 i 

 5 



1 10 



(Esti- 28 

 mate) 

 from 

 dip 



1 



8 



1 3 



'F' of F.B. 

 near viaduct 

 on G" map. 



Limestone shales, thicker bedded \ 



towards base. 

 Posidunomya Becheri (numerous in 

 J, i" layer). 



V p. inemlranacea (large) nnmerous. 

 P. memhronaeca (small) abundant 



in thin layers. 

 Large-bullion bed. Section ' T,' 6" map. 



Thinly bedded black shales, weather- 

 ing into fine flakes ; no fossils ob' 

 served. 



Strong limestone shales, compact, 



fine material ; few fossils ; occa» 



sionally Posidoniella Ircvis. 

 Ten feet thickly bedded limestone 



shales, which ring like a tile when 



struck with hammer. 

 Six-foot shales with layers of Pod' 



doniella leevis. 



Bullion bed; bullions large, cherty\ 

 crowded with Glyjjhioceras retu 

 culatniii; weathered by water ,,„.„■, „ -,, 

 have a dull glaze; in centre of y- ^^^^^^d on 6 

 bullions is a thin layer 1" which ^''■P' 

 weathers white. This layer is 



( Base of series 

 -| seen in this 

 ( locality. 



Locality 



Section 'I' on 

 G" Map: 



parallel to bedding plane. I 



Thinly bedded black shales. 

 4. Section on Hiver iVoe. 



Platy shales. "^ 



Shales with reed -like plants. 

 Limestone shales. Posidoniella 



Itevis. 

 Hard limestone band, Posidoniella 



leevis abundant. 

 Green shales. Actinopteria jjersnl- 



cata (numerous). Plants (ferns), 



INeuro^rterls antcccdens, Stur. 



Interval. 



Limestone shales. Posidoniella 

 leevis. \ 



Black limestone. 



Limestone shales. Posidoniella \ Back Tor 

 Irevis (large and numerous). '' 



Black limestone. Goniatites. 

 Cherty limestone. Plants. 

 Black limestone shales. Posidoniella 

 Iccvis (small and numerous). 



Bridge. 



