J. T. Stohbs — On AntJiraeomya Phillipsi. 507 



there was not enough evidence at the section to determine whether 

 this juxtaposition of Permians and Coal-measures represents a post- 

 Permian fault or simply a steep bank-side of eroded Coal-measures 

 against which the Permian Yellow Sands were deposited. The- 

 colliery workings, however, should definitely settle the matter. 

 The following is the section of Coal-measures at this point : — 



ft. in. 

 Grey laminated shale 

 Dark shales with nodular bands of ironstone [A. FhilUpsi, 



G. vinti, etc.) ... ... ... ... ... ... 3 



Grey gritty shale ... ... ... ... ... ... 1 6 



Grit 3 



Laminated arenaceous shale 2 + 



Kirkby gave the position of these beds as not much more than 

 fifty or sixty feet from the top of the Coal-measures, but this datum- 

 line is a very uncertain oue, owing to the pre-Permian denudation 

 of the Coal-measures in the great Northern Coalfield. The most 

 satisfactory method is to fix the horizon with respect to one of the 

 well-known coal-seams of the Durham Coalfield, and the writer is 

 indebted to Mr. Mark Ford, of Washington Collieries, who is 

 familiar with the ground in question, for the information that the 

 Hutton seam lies almost flat at a depth of about 1,700 feet in this 

 locality. The measures are at the surface, almost at the deepest part 

 of the coal-basin. 



From the ironstone bands the writer collected : — 



Anthracomya PhilUpsi (Wni.). Abundant. 

 *Carhonicola vinti (Kirkby). Abundant. 

 *Beyrichia arcuata, Salt. Not common. 



Carbonia sp. Not common. 



Spiro7'bis sp. Not common. 

 *Neuropteris gigantea, Sternb. Not rare. 



Those marked with an asterisk were recorded by Kirkby, together 

 with Diplodus gibbosiis, Ag., and other fish-remains. In addition 

 he mentions Anthracomya acuta. Dr. Wheelton Hind, however, is 

 unacquainted with this species, and very curiously, after talking the 

 matter over with Mr. John Ward, F.G.S., that gentleman showed the 

 writer a specimen of the ironstone containing G. vinti given to him by 

 Kirkby, and on the outside of tlie nodule, hitherto unrecognised, were 

 numerous individuals of A. Phillipsi. There is no doubt, therefore, 

 that Kirkby 's A. acuta should have been referred to A. FhilUpsi. 



The interest of the discovery lies in the proof of the existence of 

 the Fhillipsi-zone near the top of the Coal-measures in the Durham 

 Coalfield, and, so far as we may legitimately infer from the character 

 of the immediately-overlying measures in other coalfields, that in 

 all probability the pre-Permian denudation did not remove much 

 of the Coal-measures that are of special commercial value, but, on 

 the other hand, it has rendered the excellent coal-seams of that 

 district much more accessible. The writer desires to thank 

 Dr. Wheelton Hind for verifying the naming of the Lamellibranchs 

 mentioned in this note ; this discovery is the natural outcome and 

 verification of principles laid down by him. 



