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THE GEOLOGIST. 



The lowest of the gannister series, which is a four feet coal, identical with, 

 the Spa Clough bottom bed, is perhaps the most interesting, on account of its 

 fossils, of any mine in the Burnley measures. 



Its roof consists of a thin stratum of very fine black shale, of about four 

 inches, in which there are embedded large numbers of very fine shells, in a high 

 state of preservation, of the Buccinum, Pyramis, Catillus, Bellerophon, &c, 

 together with the jaws, teeth, and scales of fishes. This thin stratum of shale 

 is succeeded by another shale (the pecten), in which the conditions of life have 

 been entirely changed ; the Bellerophons, &c, which were so numerous in the 

 preceding shale, have been entirely swept off, and their places supplied by 

 immense numbers of Pectens, Goniatites, and Orthoceratites. 



The pecten shale reaches a thickness of several feet, and is followed by a 

 third shale, in which the conditions of life have been once more changed ; the 

 only representatives found in this shale of the immense number of shells that 

 inhabited the waters by which the pecten shales were deposited, being a few 

 very large Goniatites, which appear to have survived the changes that destroyed 

 their predecessors. 



In the last-mentioned, or third shale, there are embedded small ironstone 

 nodules, in which are enclosed very small, but very elegantly marked, Gonia- 

 tites, specifically distinct from those of the preceding shale ; others of these 

 balls, when broken, exhibit entire specimens of ganoid fish. 



It is w r ell known in some localities as the " Bullion Coal," in consequence of 

 being interspersed with pyritous nodules, called by the miners " bullions," some 

 of which contain Sigillaria, Lepidodendra, and other coal-measure plants, in a 

 high state of preservation. 



One hundred and forty feet above the bullion coal, there lies the middle coal 

 of the Gannester series, or Spa Clough top bed, which is succeeded at a dis- 

 tance of twenty-one feet by the foot mine, with a hard gannister floor. 



In the roof of the former of the above coals there have been found some 

 very fine rays of the Gyracanthus, also teeth of Rhizodus, Megalichthys, and 

 Holoptychius, together with scales, plates, jaws, bones, &c. Also, six hundred 

 and seventy-five feet above the gannister, the Arley series of coals occurs, con- 

 sisting of the Habergham, or Arley mine, four feet ; the Dandy, three feet ; 

 and the China, two feet. From the bone-bed in the black shale roof of the 

 lowest, or Arley mine, which is the most valuable of the Burnley mines, splen- 

 did specimens of fish remains of the genera MegalicMhys, Rhizodus, Diplodus, 

 &c, have been collected. 



The distance from the Arley to the lowest mine of the Burnley higher series 

 is about four hundred and sixty feet. It is a four feet coal divided into two 

 seams by a bed of " Bing," in which, lying in heaps, are embedded coniferous 

 fossil fruit of the genera Trigonocarpum. The roof of this coal contains a 

 small species of Anthracosia, also some good Lejpidostrobi, enclosed in ironstone 

 nodules. 



The next higher coal is about two and three-quarters feet thick, and identical 

 wit h the Fulledge thin bed ; it is exceedingly rich in ichthyological remains. 

 The parting between the coal and roof has yielded very fine jaws, teeth, scales, 

 and vertibral bones of the Megalichthys Hibbertii, also very perfect teeth of the 

 Ctenoptychius pectinatus, C. apicalies, together with rays belonging to the 

 Gyracanthus, Hybodus, Pleur •acanthus, &c. The roof of this coal is a very 

 finely laminated black shale, replete with the remains of fossil fish, some of 

 which were examined during the Association Exhibition in the Free Trade 

 Hall. Manchester, by Sir Philip De M. G. Egerton, M.P., F.R.S., F.G.S., &c, 

 and the Earl of Enniskillen, D.C.L., F.R.S., &c., and have been declared by 

 the above eminent ichthyologists to be entirely new to science. It also con- 

 tains a very attenuated-looking bivalve-shell. 



