﻿60 BRITISH FOSSIL TRIGONIiE. 



in T. Painei, and as the latter species has not been obtained at AncUff, which was the 

 locality of Sowcrby's little specimen, it is more probable that T. cusjjulala is the 

 young of T. Mordoni in a more dwarfed condition than has been obtained at IMinchin- 

 hampton. 



Adult examples of T. Painei are most nearly allied to T. fleda, to which the reader 

 is referred. 



A shell figured by Messrs. Rigaux and Sauvage as a variety of T. Anluenna, Buv., in 

 their interesting Memoir on new species from the Bathonian formation of Boulogne 

 ('Mem. de la Soc. Acad, de Boulogne,' 1868, vol. iii, pi. vi, fig. 4), appears nearly 

 allied to, and perhaps is not really distinct from, T. Painei. Our Plate XII, fig. 3, 

 which presents an approximation to the Boulogne shell, represents the most common 

 aspect of the species in the Great Oolite of Minchinhampton, or perhaps with the costse 

 more than usually prominent ; not unfrequently, however, the posteal varices are 

 more imperfectly developed, or more nearly resembling the figure of Messrs. Rigaux 

 and Sauvage. 



T. Arduenna, Buv., a much smaller species, is less short in its general figure, 

 with much more mmierous and more closely placed costae and varices ; the rugose area 

 is another distinctive feature. 



Dimensions. — Our largest specimen has the length upon the marginal carina of 2^ 

 inches ; the opposite measurement is 2 inches ; the convexity of a single valve 7 lines ; 

 the length of the escutcheon 1 8 lines. 



The name is intended as a slight recognition of the success which has attended 

 the exertions of Dr. Paine, of Stroud, as Honorary Secretary of the Cotteswold Naturalists, 

 Field-Club during a long period, and also of his acquirements in the cultitivation of the 

 natural Sciences. 



Stratif/raphical position and Localities. In the Great Oolite of Minchinhampton 

 Common, in the beds called " planking," where the species occm-s of every stage of growth, 

 and lis not infrequent, the valves are always disunited, and are often abraded, or have the 

 ornamentation scarcely perceptible. It has also been obtained in the Great Oolite 

 of South Lincolnshire. The specimen figvu'ed by Messrs. Rigaux and Sauvage, from 

 Boulogne, is stated to have been procured in the zone with Clypeus Plotii. The British 

 Museum has fine examples from the Great Oolite of Normandy. 



Trigonia producta, Lye. PI. XIII, figs. 1, 2, 3, 4. 



Trigonia froducta, Lycett. Note in Wright's Memoir on tbe luferior Oolite, 



Quart. Jour. Geol. Soc, 1859, vol. xvi, p. 45. 



Shell ovately trigonal, somewhat depressed, elongated posteally, short but curved 



