220 CRETACEOUS LAMELLIBRANCHIA. 
1864. Sorten pupinianus, F’. J. Pictet and G. Campiche. Terr. Crét. Ste. Croix 
(Matér. Pal. Suisse, ser. 4), p. 29. 
1897. ~ — R. B. Newton. Proc. Dorset Nat. Hist. and Antiq. 
Field Club, vol. xviii, p. 93. 
Description.—Shell elongate, more or less oblong, shghtly convex, compressed 
near the antero-dorsal margin, considerably inequilateral. Dorsal margin nearly 
straight. Anterior end rounded, not so high as the posterior part of the shell. 
Ventral margin nearly straight and nearly parallel to the dorsal margin, curving 
upwards anteriorly. Posterior margin convex, forming a rounded angle with the 
ventral margin. Umbones small, inconspicuous, situated at less than a third of 
the length of the shell from the anterior margin. 
Ornamentation consists of small concentric ridges; in some cases the ridges 
cut the posterior part of the ventral margin obliquely. A strong internal rib 
extends from the umbo ventrally, but does not reach the ventral margin. 
Measurements : 
(1) (2 (3) 
Length : : oi ; 29 ; 26 min. 
Height : , 10 ; 10 ; Orr. 
(1—3) Gault, Black Ven. 
Affinities—The occurrence of this species in the Gault of England has been 
recorded by De Rance and R. B. Newton—by the former from Black Ven, and by 
the latter from Okeford Fitzpaine. Although the example figured by d’Orbigny 
is imperfect, consisting of the posterior part of a left valve only, yet the English 
specimens agree sufficiently closely with d’Orbigny’s figure to make it probable 
that they have been correctly identified with L. Dupinianus. In most of the 
English examples, however, the posterior margin is more convex and the postero- 
dorsal angle more rounded than in d’Orbigny’s figure; but im a few specimens, 
which have been slightly crushed, these differences are not noticeable. 
The species which resemble L. Dupinianus are L. concentristriatus (Miller'), 
LL. Petersi (Reuss*), L. truncatula (Reuss*), L. Moreana (VOrbigny*) and L. limata 
(Stoliczka’). 
From the Albian of Ervy (Aube). 
Distribution.—Lower Gault of Black Ven and Okeford Fitzpaime. Upper Green- 
sand of Devizes. Recorded by Jukes-Browne from the Gault of the Isle of Wight. 
Type. 
1 «Jahrb. d. k. preussisch. geol. Landesanst. fiir 1887’ (1888), p. 431, pl. xvi, fig. 5. 
* “Kreideschicht. i. d. Ostalpen’ (1854), p. 145, pl. xxviii, fig. 10. Zittel, ‘Die Bivalv. d. 
Gosaugeb.,’ I (1865), p. 5 [109], pl. i, fig. 3. 
3 «Die Verstein. der bohm. Kreideformat.,’ pt. 2 (1846), p. 17, pl. xxxvi, figs. 18, 16, 17. 
4 «Pal. Franc. Terr. Crét.,’ vol. iii (1845), p. 324, pl. cccl, figs. 8—10. This species has been 
recorded by Barrois from the Upper Greensand of Lulworth and Devizes; I have not seen any 
examples from those localities. 
> *Paleont. Indica, Cret. Fauna S. India’ (1870), p. 101, pl. i, figs. 12, 13. 
