190 NORTH STAFFORDSHIRE COAL FOSSILS. 



The New mine ironstone at Longton is not rich in fossils. 

 At Kidsgrove it contains a rare species of shell (Anthra- 

 comya pumila). At Fenton, a remarkable bed of ironstone, 

 called the New ironstone, but locally known as the Rag 

 mine, was worked extensively a few years ago. It contains 

 the most curious collection of fish remains of any bed we 

 are acquainted with. Specimens of the rare fin-spine of 

 Orthacanthus, eighteen inches in length, have been collected 

 from this bed. The Brown mine ironstone of Silverdale 

 and Apedale contains similar fossils, and there is a strong 

 resemblance in the character of the shale which goes far 

 to prove their identity It is, however, a noticeable fact 

 that the latter bed contains many perfect fishes, while 

 those of the former bed are fragmentary. Platysomus, 

 Amphicentrum, and Rhizodopsis are the most characteristic 

 genera of fish of the Brown mine. 



The Knowles or Winghay ironstone is rich in fossils. 

 The shale resembles that of the Deep mine, not only in 

 colour and texture but in the general character of its 

 organic remains. There is, however, one striking difference, 

 that while Palasoniscus is the most characteristic genus of 

 the latter bed, Platysomus is of the Knowles. The iron- 

 stone occurs in several bands, separated by beds of shale. 

 The upper band contains the greatest number of fish- 

 remains ; the lower bands are richest in Mollusca. This 

 division contains two remarkable beds which show the 

 great range in time over which the existence of many of 

 our coal-measure fossils extended. Not only does it show 

 this fact, but it shows that important changes took place 

 during the deposition of these coal measures. The first 

 bed is that known as the Priorsfield ironstone, above 

 which there is a bed of brown-coloured stone containing 



