﻿540 MR. A, WILMOKE ON THE CARBONIFEROUS [Nov. I9IO, 



and Swniden Quarry (Swinden, near Grassington) on the one hand, 

 and the dark, evenly-bedded foraminiferal limestone of Swinden 

 Gill on the other. Between these extremes there is a complete 

 series of gradational types. 



The greyish-white very fossiliferous limestone occurs in the 

 knoll regions of Cracoe, Thorpe, and Linton (as also those of 

 Clitheroe, Slaidburn, etc., outside the region here discussed) ; and 

 it appears occasionally in other places, as, for example, at Fogger 

 near Coniston Cold, at Crag Laithe near Bell Busk, and at Slack 

 near Newsholme. The rock at Fogger is known as the ' white 

 rock ' by the quarrymen and roadmenders of the Coniston district. 



I have been working at the limestone of the Craven Lowlands 

 for several years, in the hope that some contribution may be made 

 to our knowledge of the vertical and lateral distribution of the 

 commoner fossils. It has seemed advisable that much patient and 

 careful collecting should be done, in order that comparisons may be 

 instituted between this complicated district and other Carboniferous 

 Limestone districts in which the sequence can be readily determined. 



Many of the fossils in our museums, and some of those figured in 

 memoirs and monographs, have no very definite locality assigned to 

 them, but are described as from Clitheroe, Bolland, or Craven, as the 

 case may be. In any good zonal work it is manifestly necessary 

 that the exact quarry or other exposure should be specified. 



The area under discussion falls within the 1-inch Geological 

 Survey map, Sheets 60 & 61 (southern part of the maps). It 

 must, however, be pointed out that the deep blue and the lighter 

 blue colouring have not been uniformly used by the officers of the 

 Survey. In the neighbourhood of Grassington, the deep blue is 

 used for the very fossiliferous grey limestone. In the Hetton and 

 Winterburn district it represents dark blue flaggy limestone with 

 Caninia gigantea, Syringopora, and other fossils which are found in 

 the limestones of Coniston Cold and Swinden Moor. These latter 

 limestones are coloured light blue. In the adjacent district dark 

 limestones with abundant shales are coloured dark blue (see 

 Thornton, Bain Hall, and Gisburn on the 1-inch map, Sheet 68). 



The rock at or near the dip-mark 30° IS", east of Owslin Barn is 

 apparently of exactly the same type as the rock at the dip-mark 

 65° N. immediately north of Hetton village, but the colouring 

 is different. So also the rock at Swinden Moor Head is in no way 

 different from that of Swinden Gill Head and in other exposures in 

 the 'rolling' ground near the Skipton-Helli field Boad : yet the 

 former is coloured on the map deep blue, the latter light blue. 

 The limestones of Warrel Quarry and Bell-Busk cutting are litho- 

 logically the same as the beds near Winterburn Chapel : yet, again, 

 the Survey map-colouring is different, the beds at Winterburn Chapel 

 being coloured dark blue, and those of Warrel and Bell-Busk cutting 

 light blue. 



In the present paper, as in my paper on Thornton, Marton, and 

 Broughton district, I shall describe the various exposures, giving 



