20 MR. E. A. NEWELL AEBEE ON THE [Feb. IQO3, 



rrom the Sandstone Series, and also from the Productive Measures, 

 have been recorded from the Middle Coal-Measures of Yorkshire, 1 

 and the great majority also from the Middle Coal-Measures of 

 Lancashire. 2 



I am happy to be able to state that Mr. Kidston, to whom I have 

 shown the evidence presented here, entirely agrees with me as to 

 the age of both these floras. m 



"o' 



(2) Lower Division, Productive Measures. 



With regard to the age of horizons in the Productive Measures, 

 below the Main Band, nothing definite is known at present. No 

 fossils of any sort have been described from these beds, and attempts 

 to obtain plant-remains have not been successful. The full extent 

 of the Middle Coal-Measures, as also the existence, or non-existence 

 of Lower Coal-Measures, has yet to be demonstrated. 



Among the many geological problems awaiting solution in this 

 district, the identification of the base of the Productive Measures, 

 the Millstone Grit, is one of the most important. After careful 

 enquiries, I find that this rock has never been identified in any 

 section beneath the Main Band at any colliery, or boring, in 

 this district of the Cumberland Coalfield. Yet in the Geological 

 Survey 1-inch Map, 3 rocks, described as Millstone Grit, are shown 

 to crop out some -A or 5 miles inland from the coast, from Whitehaven 

 to Workington. The base of the Productive Measures is therefore 

 at present undefined. In two localities at least: — at Harrington, 

 and recently in the Ladysmith Shaft of the Croft Pit, Whitehaven, 

 a limestone, presumably to be regarded as Carboniferous Limestone, 

 has been reached below the coals. In the latter case 4 the lime- 

 stone was first reached at 327 feet below the Main Band, and 

 between these two horizons, arenaceous and argillaceous rocks 

 occurred in nearly equal proportions, and also several coal-seams. 

 The boring ended at a depth of 89 feet beyond the first limestone, 

 passing through sandstones, shales, and several other limestone- 

 bands. The above record may serve as an illustration of the 

 uncertainty, which at present prevails, as to the base and extent of 

 the Productive Measures. 



IY. Conclusions. 



The chief conclusions, based on the discovery of fossil floras in 

 the Lower Division of the Sandstone Series, and in the Upper 

 Division of the Productive Measures,_are that both these divisions 

 are of Middle Coal-Measure age. Consequently the change in 

 lithological conditions, which resulted in the deposition of the 

 Sandstone Series above the Productive Measures, took place in 

 Middle Coal-Measure times. Also, since there was a considerable 

 accumulation of both types of deposit during that period, the 



1 E. Kidston (90). 2 Id. (92). 



3 Quarter-sheet 101 S.W. 1895. 



4 From particulars kindly supplied by Mr. James, Secretary of the 

 Whitehaven Colliery Company. 



