Oolitio Formations in the vicinity of Minchinhampton. 25 



of this form, it would be unwise to speculate upon its affinities unless with 

 great reserve and circumspection. The mode in which the markings of the 

 TrigonioB are transferred to this shell renders it very difficult to imagine 

 that it could have been a bivalve. We look as it were upon an impression 

 at the back of the paper, the parts in relief having been stamped through 

 it, but disguised by the finely striated surface at the back of the attached 

 shell. It was sedentary, and if univalve may have belonged to those forms 

 of the Patelloidea in which the shell is partially enveloped in the soft parts 

 of the animals, examples of which are found in Fissurella, HaliotU, 

 Sigaretus, and Sttmiatia. We would however wish it to be understood that 

 these hints are thrown out chiefly to engage the attention of others, as we 

 are by no meaus satisfied with the result of our own observations. 



The estuary waters which entombed the varied remains at Stonesfield 

 spread out partially a thin stratum of their muddy deposit to this neigh- 

 bourhood, without carrying with it any of the forms for which that locality 

 is so famous. Our Stonesfield slate has a few marine shells, among which 

 are Ammonites coronatus (Orbigny), A. Lalandeanw (Orbigny), Mya 

 margaritifera (Young), Ceromya V. scripta (Cardita, Buckman), Cardium, 

 new species, Anatina undulata (Sanguinolaria, Phillips), Mya dilata 

 (Phillips). As regards this neighbourhood, it may be stated as a general 

 rule, that where the lower beds of Great Oolite are shelly, they repose 

 immediately upon Fuller's earth ; in the other condition the base is 

 Stonesfield slate ; probably the fine mud of the latter deposit was carried 

 out to great depths almost beneath the region of shells. Our Fuller's earth 

 is very imperfectly exposed, nor have any considerable number of species 

 been obtained from it. The little Ostrea acuminata is found in great 

 masses, which nearly composes the beds where it occurs. Not a single shell 

 has been found peculiar to these beds. 



The Inferior Oolite in the division of its beds in this locality does not 

 differ materially from the description given by Mr. Buckman in his " Geology 

 of Cheltenham," except towards the lower portion, which is strikingly 

 dissimilar. It is not our intention to do more than allude to these 

 conditions ; a careful survey along the outer escarpment of the Cotteswolds 

 would be required to enable us to understand the changes of mineral 

 character, fossil contents, and perhaps thinning-out which certain beds 

 must undergo in their short course between Painswick and Crickley Hill. 

 Many doubts liave been expressed by persons both in the metropolis and 

 provinces as to the geological position of the rock from whence our Great 

 Oolite fossils are derived ; ttiese doubts would seem to have arisen from a 

 resemblance which portions of our rock and its fossils bear to a certain bed 

 of the Inferior Oolite near Cheltenham. 



Of the geological position of the rocks in our neighbourhood no person 

 who has examined them can entertain any doubt; our sections, both natural 

 and artificial, are numerous and of a decided character, affording what 

 can rarely be seen elsewhere in one view, a complete escarpment from the 

 Great Oolite to the Lias inclusive. The shells of the upper rag-stone agree 

 closely with those from the Cheltenham sections. The cream-coloured 

 marls and marly rock called " Fimbria bed," have however disclosed a 

 remarkable suite of shells which must not be passed over in silence. The 

 general aspect of these fossils, as contrasted with those of the upper and 

 lower rag-stones, is striking. The association of genera strongly reminds 

 us of the Great Oolite. The genus Nerinea, which is very rarely seen in 

 the rag-stones, again reappears in vast profusion, to such an extent indeed 

 that in some localities almost every fragment of marly rock discloses 

 sections of this extinct form. Accompanying these are several species of 

 small Cerithia, together with an equal variety of the genus Chemnitzia t 

 comprising some of the most slender spirial univalves which it is possible 

 to imagine. The Host rot rcmcc, though rare, are likewise represented by 

 five species. We seem in fact to have a repetition of the circumstances 

 under which the mollusca of the Great Oolite lived and multiplied. In a 



