136 GUIDE TO THE EOSSIL INVERTEBEATE ANIMALS. 



Gallery^ ^ their ornament. Adjoining these are shells from the Kella- 

 ways Eock, a brownish sandstone at the base of the Oxford 

 Clay, giving a name to the Callovian Age. Among these 

 are Gryijliaea hilohata with a curious fold on its side, Isocardia 

 minima, and Goniomya 'Y-scripta. 



The shells of Bathonian age are arranged under the 

 formations from which they come. First are those from the 



Table-case widely distributed rubbly limestone called Cornbrash, which 

 11- has yielded the scaphopod Dentalium annulatum,, the 

 gastropods Bvlla undidata, Pseudomelania vittata, and the 

 lamellibranchs Chlamys [Feden^ vagans, Lima ditplicata, 

 Pseudomonotis [Avicula~\ ecJiinata, and several Trigonias. 

 Many of the specimens are figured in Blake's " Monograph 

 of Cornbrash Fossils." There are very few shells from 

 the Forest Marble, but among them is a fine example of 

 Trigonia detrita figured by Lycett. In the equally small 

 series from the Bradford Clay, one may notice a set of 



Table-eases Oxytoma [Avicida] costata. The Great Oolite shells are 



11 & 12. i;^-^Qg|^}y from the Oolitic freestone. Here is the type-specimen 



of Pteroccra Wrighti, a fine winged shell ; then several 

 species of Pitrpuroidea, among which P. morrisea with its 

 heavy spines is conspicuous ; several limpets, Patella, testify 

 to the rocky nature of the sea-floor ; Nerita rugosa seems 

 to show bands of colour, and such are still more evident in a 

 large form of Natica. Among lamellibranchs one may note 

 Lima cardiiformis, Pteropema costatida, Pinna ampla, 

 Parallelodon [Macrodon'\ liirsonensis, and the massive Pacliy- 

 risma thick support ") grande. The Stonesfield Slate 

 yields Trigonia imidrcssoj and Pinna cuneata. The small 

 series from the Fuller's Earth includes Volsella [Modiola] 

 imhricata and Ceromya plicata. 

 Table-eases Next come shells from the variable series of marine 



12 & 13. limestones known as the Inferior Oolite, deposited mainly 



in Bajocian time. The chief localities in the south-west 

 of England here represented are Dundry near Bristol, Half- 

 way House near Yeovil, Bradford Abbas, and Leckhampton 

 Hill near Cheltenham. These have yielded a fine series of 

 PleuTotomaria, many species of Amherleya, Pseudomelania, 

 Purpurina, Dclp)hinula, Ccrithium, Cirrus, Nerinaea, Alaria, 

 and other gastropods. Certain species of Amherleya, Ceri- 

 tJiium, Onustus, and Ncridomus acquired an interest a few 

 years ago from their resemblance to some shells now living 

 in Lake Tanganyika; but it is not now imagined that 

 the animals themselves had the same structure. Similar 



