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ME. B. KIDSTON ON THE DIVISIONS OF THE [May I905. 



Series, as there is no area in which this series is better developed 

 than in Lanarkshire. 



This change of nomenclature is absolutely necessary, as the 

 terms 'Upper,' 'Middle,' and 'Lower' Coal-Measures have been so 

 loosely applied in the past, that in many cases these terms have 

 only a local significance, having been applied to rocks of different 

 ages in different districts. It is therefore necessary, in order to 

 avoid further confusion, to introduce a new and distinctive termin- 

 ology for the various divisions of the British Coal-Measures. 



These proposed changes are shown in the following tabular 

 form : — 



Coal-Measures. 



Upper Coal-Measures "= /^dstockian Series 



I (including the Keele Group). 

 Transition Series = Staffordian Series. 



Middle Coal-Measures = Westphalian Series. 



Lower Coal-Measures 1 T , . „ 



(including the Millstone-Grit). / = Lanarkian Series. 



Before concluding this paper, I wish to refer to an interesting 

 pit-sinking made at Bradford Colliery, Manchester, last year, at 

 which the fossil plants were carefully collected from the shales 

 associated with the Bradford Four- Foot Coal. A considerable 

 number of specimens from these shales were submitted to me for 

 examination by Mr. W. Hemingway and Mr. P. Whalley. A list 

 of the plants from this sinking has already been published by 

 Mr. John Gerrard, along with a section of the strata from which 

 they were derived. 1 



I append a list of the species contained in the collections examined 

 by me ; they were derived from shales extending from 24 feet to 

 about 321 feet above the Bradford Four-Foot Coal. 



A comparison of this list with the species noted from the Black- 

 band Group will show the great similarity of the two floras. 

 There are still here two species, JSphenojohyllum emarginatum, 

 Brongn., and Annularia sphenopliylloides (Zenker), characteristic 

 of the Upper Coal-Measures, and some which are common to 

 that horizon ; but these are accompanied by an overwhelming pro- 

 portion of species characteristic of the Middle Coal-Measures. The 

 plant-evidence, therefore, indicates that the rocks from which the 

 specimens came at Bradford Colliery belong to the Blackband Group 

 of the Potteries Coalfield, and that the Bradford Four-Foot Coal 

 occurs at the base of the Group, and would therefore occupy a 

 position on or about the horizon of the Bassey-Mine Ironstone and 

 Coal of the Potteries Coalfield. 



1 ' Notes on Fossils found above the Bradford Four-Feet Coal at Bradford 

 Colliery, Manchester' Trans. Manch. Geol. & Min. Soc. vol. xxviii (1904) 

 p. 555. 



