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BRITISH FOSSIL TRIGONLE. 



little memoir on the Geology of Banbury (Warwickshire Nat. Field Club, 1872) ; the 

 numerous Inferior Oolite fossils recorded at the locality in question contain Trigonia 

 costata, T. signata, T. formosa, and T. Phillipsi, the last named being intended for the 

 present species ; the locality, with a list of the fossils, is also mentioned by Prof. J. W. 

 Judd, in the 'Memoirs of the Geological Survey' (Rutland, &c), pp- 23 and 25, 1875, 

 and in Phillips's ' Geology of Oxford,' Appendix b, p. 512. The other specimen figured 

 agrees entirely in its aspect and matrix with the Milcomb specimen, and I have no 

 doubt pertains to the same rock ; it belongs to my collection, but unfortunately no note 

 has been retained of the locality. 



The small specimen figured by Quenstedt is slightly more lengthened, but offers no 

 other material distinction ; it possesses some differences with the T. striata of the same 

 author (' Jura,' pi. xlvi, figs. 2, 3) ; both forms are sufficiently distinct from the 

 specimens figured in the • Mineral Conchology.' 



Trigonia Keepingi, Lye, sp. nov. PI. XXXV, figs. 1, 2 (Clavellat^;). 



Shell with the general figure much shorter and more convex than T. ingens ; it has 

 also much greater breadth across the pallial surface of the valve ; the escutcheon is 

 depressed, of moderate breadth, its upper border is somewhat raised. The area is com- 

 paratively narrow and slightly convex or raised ; it has a well-marked median furrow ; it 

 is crossed by some irregular and unequal plications, which differ much in prominence 

 upon the two specimens at my disposal. The marginal carina is represented by a row 

 of large rounded, or ovate, closely arranged nodes ; there is a row of minute papillary 

 prominences at the position of the inner carina, but the area generally is irregular in its 

 ornamentation. The other portion of the valve has the rows of costae very numerous, 

 regular, and closely placed ; they meet the carina at a considerable angle and have only 

 a small curvature ; the nodes in the rows, sixteen or more in each, are nearly equal in 

 size, rounded, prominent, and very closely arranged those ; of the last-formed two or 

 three rows become ovate ; their longer diameters are across the rows. Upon the whole 

 the rows diminish somewhat in size near to the marginal carina. T. ingens, Lye, and 

 T. Keepingi, Lye, represent the only examples of the Clavellata known in the Cretaceous 

 Rocks. 



The name adopted for this species is that of the able Curator of the Woodwardian 

 Museum, Cambridge, who obtained the specimens in the Middle Neocomian formation 

 at Acre House near Tealby, and kindly brought them to my notice. For ample infor- 

 mation respecting the geological position of the Tealby beds and their relations to 

 Neocomian strata at other localities refer to three memoirs by Prof. J. W. Judd, ' Quart. 



