474 



FOSSIL ANIMAL REMAINS IN THE COAL-FIELD. 



lieries, the detail of the beds annexed is in many respects peculiar and unknown in other 

 parts of the field. (See sections, p. 480.) 



These sections exhibit many repetitions of strata, which slightly differing from 

 each other in mineral ingredients, and succeeding each other in finely laminated 

 beds of different colour, must have occupied a very lengthened period in their accumu- 

 lation. In pointing out the discrepancies in mineral characters between strata of the 

 same age in different parts of the field, it is obvious, as before stated, that such phe- 

 nomena are strictly analogous to what we should suppose to have resulted from the 

 circumstances under which such strata were accumulated. (See pp. 149 et seq.) 



This northern part of the coal-field is interesting to geologists, not only as abounding 

 in well preserved impressions of plants (for these are common to all coal-fields), but in 

 containing a considerable number of animal remains which are of rarer occurrence in 

 the southern tract 1 . These consist of several species of Uniones and fishes, some of which 

 appear in the ironstone concretions, but the greater part are found in the beds of black 

 " bat'' a dull, compact, bituminous shale, which sounds under the hammer like wood, 

 and splits into flat and thinly laminated fragments. The Uniones occur in great quan- 

 tities in some of the old works in the western slopes of the Birch Hills, near Bentley 

 Hills, and also in the Lanesfield collieries. They consist of several species which have 

 been examined by Mr. J. Sowerby, some of which are new and will be published in the 

 Mineral Conchology. 



At Lanesfield, these shells are associated with the remains of several genera and species 

 of fishes, which, according to M. Agassiz, are 



Megalichthys Hibberti, Agassiz. 

 Megalichthys Sauroides, Agassiz. 

 Diplodus gibbus, Agassiz. 

 Coprolites of fishes and scales, &c. 



These organic remains are of great interest, in establishing a geological identity 

 between the coal measures of the Dudley district and those of distant parts of Great 

 Britain. The same species of fishes, associated with scales, teeth, coprolites, &c, are 

 here found commingled in a finely levigated, hard, black shale 2 , precisely similar (I 

 speak in both cases from personal comparison) to that in which they were first dis- 

 covered by Dr. Hibbert at Burdie House near Edinburgh, and I have no doubt that an 

 assiduous fossil collector in the Staffordshire field would discover many more of the 

 species which occur in the rich emporium of the Scotch coal measures. That these re- 

 mains have also been deposited in the adjacent coal-fields of north Stafford 3 (Newcastle 



1 I have just been informed, and therefore too late to become acquainted with the species, that Mr. Black- 

 well of Dudley possesses some fine specimens of fishes from the Dudley coal-field. 



2 The bat of Staffordshire. 



3 T have indeed myself received specimens of this coal tract from Mr. Garner, among which, besides the two 

 common species of Megalichthys, Professor Agassiz recognised Holoptychm, another of the genera found at 

 Burdie House, but of a new species, to which I hope he may assign the name of H. Garneri. 



