436 MR. 8. S. BTJCKMAN ON" THE BAJOCIAN [Aug. 1 895, 



Appendix to Paets I. & II. 



1 . The Geographical Extent of the f Intervening Beds.' 



Although the district has not heen examined in sufficient detail, 

 a few observations may nevertheless be made in this connexion. 

 There would be no difficulty in tracing the geographical areas of the 

 different ' intervening beds,' and it may be an interesting field of 

 future research. Meanwhile it may be noted that the following 

 localities show no deposit of ' intervening beds ' — namely, Selsley 

 Hill, Mount Surat, Miserden (Bull Bank), Cranham "Wood; that 

 they form, if connected by lines, a rough semicircle or rather more, 

 somewhat adjacent to the present course of the River Frome ; that 

 within, namely to the north-east of this semicircular line, the ' inter- 

 vening beds ' (the semicircle being their boundary) extend till they 

 are cut off by the escarpment of the Hill-flank overlooking the 

 Severn Valley. 



Then there is another line which begins at Birdlip, with no inter- 

 vening beds, and this probably goes south of Bendcomb, 1 certainly 

 south of Chedworth Wood, where the ' intervening beds ' are so well 

 developed (see p. 425), and afterwards must bend to between 

 Harford and Little Bisington, for at the latter place Clypeus-gr'ib 

 rests on clay — presumably Upper Lias. 2 Thus the ' intervening 

 beds' of the Middle and Northern Cotteswolds are cut into two 

 parts by a trough with a north-westerly direction at Birdlip, and 

 they are bounded by two arcs radiating thence to the south-east and 

 north-east respectively. 



2. The Geographical Extent of the Witchellia-gr'it. 



It is reasonable to assume that the WitcheUia-grit extended over 

 as wide an area as the other 'intervening beds,' and therefore it 

 would have occupied a large portion of the Mid-Cotteswolds. It must 

 also be remembered that the sea which deposited the WitcheUia-grit 

 must have had communication with Dundry 3 and with Dorset. Now, 

 what with the Bajocian denudation from which the WitcheUia-grit 

 suffered very greatly, and with Quaternary denudation which has 

 removed it from places where it escaped the Bajocian denudation, 

 this deposit occurs in the Middle Cotteswolds over a very limited 

 area. It is evident that the Bajocian denudation removed it from 



1 A roadside section at Rendcotnb afforded, so far as I could ascertain, only 

 7 inches of Lower Triffonia-grit as the 'intervening bed,' and this was much 

 bored ; but it may be remarked that the section is much overgrown, and no very 

 definite palreontological evidence was obtained. 



2 Hull, 'The Geology of the Country around Cheltenham,' Mem. Geol. Surv. 

 1857, p. 47. 



3 From Cold Comfort to Dundry is a distance of 42^ miles direct, and no 

 WitchelHa-be&s occur in the interval ; but the connexion may not have been 

 direct. 



