264 MR. E. WITCHELL ON THE BASEMENT- BEDS 



20. On the Basement-beds of the Inferior Oolite of Gloucester- 

 shire. Ey E. WiTCHELL, Esq., E.G.S. (Eead Eebruary 24, 

 1886.) 



During the last twenty years very little has appeared in the Journal 

 of the Geological Society upon the Inferior Oolite of Gloucester- 

 shire. Prior to that period the Journal contains several valuable 

 papers on that formation by able geologists, among whom I may 

 mention the names of the Rev. P. B. Brodie, Dr. T. Wright, Pro- 

 fessor J. Buckman, Professor E. Hull, and Dr. Holl. In addition 

 to these papers we have the Memoir of the Geological Survey by 

 Professor E. Hull, ' The Geology of Cheltenham,' and Dr. Lycett/s 

 ' Geology of the Cotteswold Hills,' — works which have served as 

 guides to the Cotteswold geologist to the present time. Indeed the 

 work done between the years 1847 and 1860 was of such great 

 extent and excellent character that it seemed as if there was nothing 

 more to do in the Cotteswolds except, perhaps, to make from time 

 to time some addition to the lists of fossils of the district ; but after 

 working over the Inferior Oolite of the Cotteswolds nearly a quarter 

 of a century, and going carefully over the work of my predecessors, 

 I am of opinion that another paper at least is required upon the 

 lower beds of that formation before they can be thoroughly under- 

 stood. My reasons for this opinion are : — (1) That the beds 

 called *' Pea Grit " in the Leckhampton section by Hugh Strickland, 

 which name was adopted by Dr. Wright and the Geological surveyors, 

 include in that term — erroneously, as I think — all the beds occur- 

 ring between the Pea Grit proper and the Cephalopoda-bed of the 

 sands, which beds are shown in some sections to be more than thirty 

 feet in thickness. (2) That the use of the term " Pea Grit " in the 

 way I have mentioned has led to confusion in the description of the 

 beds extending over a large portion of the Cotteswold area. (3 ) That 

 the Pea Grit proper has a much greater extension over that area 

 than has hitherto been supposed to be the case. 



If we examine the lower beds of the Inferior Oolite in the typical 

 section at Eroceater Hill, beginning with those immediately overlying 

 the Cephalopoda-bed, we see that they consist of brown sandy lime- 

 stone in two or three beds, and above these some beds of crystalline 

 limestone about 10 feet thick, and beds of fine-grained limestone 

 about 50 feet. These beds are thus described by Dr. Wright ; but 

 Dr. Lycett, while giving a similar description of the brown sandy 

 beds, refers to the others as " beds of oolitic limestone used as a 

 freestone quarry." In the section at Haresfield Hill we see similar 

 beds, and on reference to the published sections find a nearly similar 

 description of the Cephalopoda-bed, the brown sandy limestone-beds, 

 and the oolitic limestone or freestone. At Leckhampton Hill we 

 again see these beds, but find on reference to the published works 

 that they are described as " pea grit," yet they are the same beds 



