﻿322 ME. E. KIDSTOlSr OX THE DIVISIONS OF THE [May I905, 



as well as plants, must be taken into account, and the story told by 

 each must agree in the main details, else classification, founded on 

 the study of one group alone, wouid probably lead to erroneous 

 results. It was difficult to criticize a paper from a mere abstract, 

 but the questions which at once occurred to him were : — ' How 

 sharp are the proposed lines of subdivision? Are they exact and 

 absolute ? Can they be traced from coalfield to coalfield ? Are 

 they of practical utility?' The speaker felt strongly that there 

 was no good reason for taking the Bassey-Mine Ironstone as the 

 base of a subdivision ; a similar flora and fauna occurred both 

 above and below this horizon, and he (the speaker) had made 

 his subdivision at the horizon of the Gubbin Ironstone, where 

 Anthracomya Phillipsii came in for the first time, on lithological 

 grounds. 



He entirely objected to the term Staffordian, for two reasons. 

 It was unnecessary, for there were already in use the terms Etruria 

 Marls and Blackband Series, which were more topical and 

 exact. As the Blackband Series was not developed in South Staf- 

 fordshire, the term Staffordian was inexact and included too 

 much. Indeed, used in the Author's sense, it ought to be North 

 Staffordian. 



The speaker also entered a protest against the use of the terms 

 Westphalian and Lanarkian. There was neither unconformity 

 nor faunal break in the Coal-Measures of the Midlands, and any sub- 

 division must be therefore wholly artificial and empirical. Further, 

 he did not believe that the Lanarkshire Coalfield was merely the 

 homotaxial equivalent of the lower part of the Staffordshire Coal- 

 Measures. The molluscan fauna strongly contradicted such an 

 assumption. The heresy of the subdivision into Upper, Middle, 

 and Lower Coal-Measures had taken a long time to kill, and the 

 speaker failed to see that the Author's proposition had any more 

 real basis. At any rate, in North Staffordshire there was no strati- 

 graphical or faunal evidence in favour of drawing a subdivision at 

 the Ash Coal. 



Mr. Steahan agreed with the previous speaker in deprecating 

 the introduction of the new names suggested for the subdivisions of 

 the Coal-Measures. They were inferior to the old names, in being 

 in no way self-explanatory, while they placed an unnecessary tax 

 upon the memory. 



It had been said during the evening that horizons in the Coal- 

 Measures could be determined both by plants and lamellibranchs, 

 but he would point out that a problem of the greatest economic 

 importance, which had exercised the minds of the Coal-Commissioners 

 of 1871 and of mining engineers ever since, remained still unsolved. 

 The difficulty lay in correlating the Measures proved at Bradford 

 with those at Astley, and in determining the relative positions of 

 the Bradford Four-Foot Seam and the Worsley Four-Foot Seam. 

 There were more than 3000 feet of strata in question. So far, they 

 had been told that the Bradford Seam was associated with plants 

 of ' Transition ' (Staffordian) type, and a correlation was suggested 



