1859.] WRIGHT INFERIOR OOLITE. 19 



The lower Trigonia-grit, which is seen in position on the plateau 

 above, has rolled over and formed the glacis of the hill ; it has 

 thereby covered the beds of the A. JJanqdirlcsianns zone, which 

 here immediately underlie this grit. Kecent workings having 

 more fully exposed the A. Hwrrvphriesianus bed than formerly, I havo 

 collected therofrom a series of about forty species of fossils charac- 

 teristic of the zone, and have likewise ascertained the stratigra- 

 phical sequence of the beds composing this middle subdivision in the 

 Northern Cotteswolds. 



The Rolling-bank Quarry is capped by about 18 inches of tho 

 lower Trigonia-grit, consisting of loose, incoherent fragments of a 

 light-coloured oolitic limestone, beneath which are exposed the 

 uppermost beds of 



The Ammonites Humphriesianus Zone. 

 No. 1. The Terchratnh i Fhillipsii Bed is a light buff-coloured 

 compact earthy limestone ; many of the blocks are almost entirely 

 composed of the shells of Bruchlopoda, of which that of Terebrutnhi 

 Phillipsii greatly predominates. The bed measures from 2 to 4 feet 

 in thickness, and contains 



Lima proboseidea, Sow. 

 Terebratala Phillipsii, Mor. 



perovalis, Sow. 



carinata, Lantk. 



Terebratula Buckmani, Davids. 

 Rhynchonella spinosa, Schloth. 



subtetrahedra, Davids. 



angulata, Sow. 



No. 2. The lioad-stone consists of a coarse, brown, ferruginous, 

 oolitic limestone, extremely hard and crystalline, traversed in some 

 parts by sandy layers, and containing in others calcareo-siliceous 

 concretions, which have a crystalline structure and unequal fracture. 

 It forms a durable road-material, and is raised for that purpose. 



It varies from 10 to 15 feet in thickness, and contains a small 

 assemblage of Molhuca, which arc nearly all in the state of moulds. 

 The upper portion of the road-stone contains a sandy stratum, in 

 which a remarkable Gastcropod, nearly identical with Melania 

 (Chetnnitzia) striata, Bow., from the Coralline Oolite, occurs in con- 

 siderable numbers. This shell has been separated from the Coral 

 Bag species by Dr. Oppel, and named ChenrnitdaSasmanrd. This is 

 tlir only bed and locality from which I know it in the Cotteswolds; 

 it is found, however, in the grey limestone at Scarborough, the 

 coi nlativc of this /one. The lower portion of the Road-stone contains 

 most of the species of the subjoined list. Trieftitet undulatus, Lyo., 



is found \eiy large, ami sometimes well presi rved in the fork, hut 



cannot be extracted entire. Pholadomya ILraulii, Ag., likewise 

 attains gigantic dimensions. 



Ammonites Orbigniazraa, Wt, (Iiron- 

 ■ii. tFOrb.) 



Iliiiiiphriesiimus, Snv. 



Brooonj 



Brnikniritliri). 



(.'hemnit/ia Sn ni.iiini, <\ 



lintat.i. 



Elsufotoinaria farmtt. Sow. 



eluli^'lila 



coii-triei:i. Dttlong. 



Tur!>o tovigatas, • s:, "•• 

 OitiM flaballoidea, Lcmi. 



, lnru'i' lint ••*!" 



Hinnitet tuberoul 



L' 



