﻿Vol. 6 1.] IN THE NOETH-STAFFOKDSHIKE COAL-MEA.SUEES. 515 



obtained were Pterinopecten papyraceus, Goniatites, and Lingula 

 mytiloides. The last-named species often occupies a distinct portioD 

 of the deposit — a peculiarity which has been previously noticed by 

 William Molyneax l and Mr. John Ward. 2 In these layers, as a rule, 

 it is not associated with any other genera (with the exception of 

 Orbiculoidea nitida). In the following horizons, it is confined to 

 the uppermost portion of the deposit, namely : — 



The Florence Marine Bed. 



The Seven-Feet Banbury Marine Bed. 



The Upper Marine Band in the Cheadle Coalfield. 



The fact that plant-remains are not rare in these horizons which 

 are so strongly marine in character, has been mentioned previously. 

 Another observation has been emphasized by these researches, 

 and that is the clear and distinct separation of the marine mollusca 

 from those fresh water forms that are so common in theCoal-Measures, 

 particularly in North Staffordshire. It is all the more necessary 

 to lay stress upon this fact, because statements to the contrary are 

 made by such authorities as Jukes and J. W. Salter respecting 

 South Staffordshire 3 ; and Prof. Hull, respecting the North-Stafford- 

 shire and other Coalfields. 4 The question in doubt, however, 

 is whether those workers examined the beds in situ, or simply 

 collected from the spoil-heaps of mines. In my opinion, there 

 is no more fruitful source of error than the latter method, 

 unless the precaution be taken, there and then, of verifying the 

 results by observation of the beds in place. This distinct separation 

 of the freshwater and marine faunas is corroborated by such careful 

 workers as Phillips in Yorkshire, 5 Kirkby in Durham, 6 Molyneux 7 

 and Mr. John Ward 8 in North Staffordshire, and Mr. George Wild in 

 Lancashire. 9 In North Staffordshire two interesting examples of the 

 close proximity, but definite separation of these faunas, have been 

 noted, namely: — The Moss-Can nel horizon and the Upper Marine Band 

 in the Cheadle Coalfield. In the former instance, it requires very 

 careful examination of the shales to be convinced of the distinctness 

 of the layers containing Myalina compressa and Carbonicola acuta. 

 When we consider the number of individuals of each class and the 

 fact that they are usually scattered through the shale, it would 

 not be surprising if an odd individual of either character should be 

 found among a colony of the other class. The same peculiarity 

 in the case of the Cheadle Upper Marine Band has already been 

 mentioned (p. 511). 



1 B-ep. Brit. Assoc. 1865 (Birmingham) p. 48. 



2 Trans. N. Staffs. Inst. Min. & Mech. Eng. vol. x (1890) p. 43. 



3 ' S. Staffs. Coalfield' 2nd ed. Mem. Geol. Surv. 1859, pp. 27, 58. 



4 Quart. Journ. Geol. Soc. vol. xxxiii (1877) pp. 628, 643. 



5 Encyclopaedia Metropolitana, vol. vi (1845) art. Geology, p. 591. 



6 Quart. Journ. Geol. Soc. vol. xvi (1860) p. 414. 



7 Eep. Brit. Assoc. 1864 (Bath) p. 343. 



8 Trans. N. Staffs. Inst. Min. & Mech. Eng. vol. x (1890) p. 31. 



9 Proc. Yorks. Geol. Soc. vol. xiii (1895-99) p. 305. 



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