﻿520 



ME. J. T. STOBBS ON THE MAEINE BEDS [Aug. I905, 



cannot agree. The fauna contained by the last-named horizon was 

 said by J. "W. Salter to be ' comparable with that of the Lower 

 Coal-Measures of Shropshire, 1 by which, I presume, was meant the 

 Penny stone of Coalbrookdale. This identification, by the evidence 

 of the fauna and the position of each horizon in the Coal-Measure 

 Series, is, in my opinion, correct. The extraordinary fauna contained 

 in these beds in Lancashire, Coalbrookdale, South Staffordshire, and 

 in the Gin-Mine or Twist Coal of North Staffordshire, leaves little 

 room for doubt that this horizon may be used as the first connecting- 

 line extending between those coalfields (A, in fig. 3, p. 518). 



The following analysis of the lists from all these districts, 

 together with the stratigraphical position of the horizon in each 

 coalfield, constitutes the justification of this conclusion : — 



North 

 Staffs. 



South 

 Staffs. 



Archazociduris I # 



Lingula mytiloides, Sow j -x- 



Orbiculoidea nitida (Phill.) { * 



Productus scabriciilus, Sow j -x- 



Ctenodonta icevirostris, Portl ! -x- 



Nuculana acuta, Sow ! -x- 



Pseudamusmm fibrillosum (Salt.) ...I -x- 



Pterinopecten papyraceus (Sow.) ... -x- 



Ephippioceras costatum, Foord * 



Orthoceras aff. ascictdare, Brown ... x 



Temnocheilus concavus (Sow.) -x- 



Conularia quadrisuicata, Sow j 



Listracantkus -x- 



OoALBROOK- 



Lanca- 



DALB. 



shire. 



-X- 





-X- 







-x- 



-X- 



•x- 





* 



* 





* 





-X- 





-x 







* 



The second line (B, fig. 8, p. 518) may be taken as the Seven- 

 Feet Banbury marine bed in North Staffordshire. Mr. Walcot 

 Gibson, of the Geological Survey, kindly showed me the marine 

 bed discovered by him in Nottingham, and reported as lying about 

 80 feet below the Furnace Coal (or 76 feet above the Blackshale 

 Coal) of that district. 2 On the occasion of that visit I expressed 

 the opinion that the suite of fossils collected from the band corre- 

 sponded most nearly with that of the Seven-Feet Banbury bed, 

 and this view has been confirmed by subsequent work. In both 

 coalfields this marine horizon is similarly situated with respect 

 to the zone of Carhonicola robusta (a good zoning form), which in 

 Nottinghamshire is found in connection with the Silkstone or Black- 

 shale Coal, and in North Staffordshire occurs near the Cockshead 

 Coal. It is most interesting to recall the fact that Henry Denny 

 in 1845 recorded the existence of a marine band containing Lingula, 

 82 feet above the Silkstone Coal, 3 verifying in a remarkable way 

 the identity of the Silkstone Coal of the Barnsley area with the 



1 ' Geology of the Country around Oldham ' Mem. Geol. Surv. 1864, p. 65. 



2 ' Summary of Progress of Geol. Surv. U. K. for 1902 ' 1903, p. 16. 



3 Proc. Yorks. Geol. & Polytechn. Soc. vol. ii (1842-48) p. 293. 



