JURASSIC AND TRIASSIC BRACHIOPODA. 147 



121. Terebratula Stephani, Dav. Sup., PI. XVIII, figs. 1 — 7. 



Terebratula stjb-maxillata, E. Desl. (not of Davidson). Brachiopodes Jurassiques, 



p. 270, pis. lxxvii and lxxviii, 18/2. 

 — Stephani, Dav. Proc. of Dorset Nat. Hist, and Antiquarian Field Club, 



vol. i, pi. i, fig. 3, 1877. 



Shell sub-pentagonal, longer than wide, strongly biplicated, widest about the middle. 

 Dorsal valve moderately convex, with two more or less prominent folds on the posterior 

 half of the valve. These rounded folds are more or less widely apart, leaving between 

 them a sinus of greater or lesser depth. Ventral valve rather deeper or more convex 

 than the dorsal one, with a more or less prominent rounded longitudinal fold, especially 

 developed in the posterior half of the valve. On either side is a deepish concave furrow, 

 corresponding with the folds in the dorsal valve ; beak incurved, foramen but slightly 

 separated from the hinge-line by a small deltidium. Loop short, surface smooth. Two 

 specimens measured — 



Length 1 inch 9 lines; width 1 inch 3 lines ; depth 12 lines. 

 16 14 10 



05s. This is the shell described and figured by Mr. E. Deslongchamps at p. 270 

 of his ' Brach. Jurassiques ' as my T. sub-maxillata, but I was able to convince my 

 distinguished friend during his visit to Brighton in 1876 that he was mistaken in his 

 identification. T. Stephani appears to be very abundant in the Inferior Oolite of several 

 localities, especially at Bradford Abbas, Broadwinsor, and several other places in 

 Dorset and Somersetshire, where Mr. Darell Stephens, to whom I dedicated the species, 

 picked up and forwarded for my examination more than two hundred specimens. None of 

 the examples much exceeded the dimensions above given. It varies very considerably 

 in shape and seems to be intermediate between Ter. perovalis and T. Phillipsii, but is, 

 even when adult, a much smaller shell. Its strongly biplicated valves distinguish it from 

 T. perovalis, and it is comparatively less broad than T. sub-maxillata. 



The Bradford Abbas specimens agree exactly in shape with those figured by Mr. E. 

 Deslongchamps from the Inferior Oolite of the Department du Calvados in France, where 

 the fossil is stated to be very abundant. The same French palaeontologist quotes it from 

 Stuiferaberg, Bopfingen, Brauweberg, Balingen (Wurtemburg), Liestal, Aaran, Switzer- 

 land, and also from Spain. 



