COTTESWOLD DISTRICT. 63 



subdivisions may be taken to represent the Glypeus-grit. Here, as elsewhere, the 

 great mass of T. globata occurs just above the Guisei-bed. This series has afforded 

 Mr. Witchell several species of Gasteropoda, including the Nerincea so often 

 mentioned and some others. As a horizon therefore it is deserving of some 

 notice. Mr. Witchell's types of N. Guisei, &c, are, I believe, from this very bed on 

 Rodborough Common. 



The next point worthy of notice is the Upper Coral-bed, which according to 

 Mr. "Witchell has its southward limits hereabouts. The Upper Trigonia-grit of 

 this section calls for no special comment. This is the bed that we have seen 

 continuously from the neighbourhood of Little Sodbury (Horton Hill) . It appears 

 to contain but few Gasteropoda here ; at least I find no great number in Mr. 

 "Witchell's collection from this horizon. For all that, I have very little doubt of its 

 being the representative of the rich shell-beds which, further south, have yielded 

 such an abundance of Gasteropoda towards the base of the ParJcinsoni-zone. 

 There are also but few Gasteropoda from the Gryphite-grit, and consequently we 

 need not take much trouble to discuss its geological position. Rodborough 

 Common is about the last exposure where it contains the characteristic Gryphite, 

 whilst further south ("Wootton-under-Edge, Horton Hill, &c.) the beds of the 

 ParJcmsoni-zone rest directly on the Cotteswold Freestones. The Gryphite-grit 

 has generally been regarded as belonging to the Humphries ianus-zone, but I leave 

 this question to be discussed elsewhere. The entire Ragstone series, or Upper 

 Division of the Inferior Oolite, on Rodborough Common measures about 23 feet, 

 whilst the section on Stroud Hill, only just across the valley, has already increased 

 to 37 feet (teste Witchell) partly owing to the expansion of the Gryphite-grit. 



Steoud, Swift's Hill, and Longeidge. — These are all on the north side of the deep 

 valley which commences at Stonehouse ; they may be taken together as constituting 

 one section, so to say, of the Cotteswold District. Swift's Hill Quarry is about one 

 and three quarter miles north-east of Stroud station near Knapp Farm. There is 

 a fault in this quarry, which is mainly in the Freestone series. The Nerincea-bed 

 occurs several feet below the soft Oolite Marl. It forms part of two blocks, and 

 the Nerinseas occupy a vertical space of about 2 feet 6 inches. The lower bed is a 

 mixture of chalky stuff and oolite, and this is the best for fossils ; sections of 

 Nerinosa are extremely numerous. The quarry at Longridge is on very high ground 

 two miles north of Swift's Hill, and about one mile east of the small town of 

 Pains wick. The quarry is in such a muddle that no section can be obtained ; but 

 the horizon whence the bulk of the fossils are obtained is probably a little below the 

 Oolite Marl. A very fine series of Nerinaeas have been procured from this place 

 lately both by Mr. "Witchell and myself. Taking Stroud Hill as the representative 

 section of the region immediately north of the great valley, we obtain the following 

 sequence. For further details I would refer to "Witchell's Geology of Stroud, p. 5. 



