94 CRETACEOUS LAMELLIBRANCHIA. 
Pictet and Campiche,' show a more elongate shell; the species is referred by these 
authors to Lithodomus. 
M. culter, Wollemann,’ from the Hils-conglomerate of Brunswick, is closely 
allied; it appears to differ chiefly in having a more angular outline and a distinct 
carina. 
Young specimens of M. equalis are similar in form to M. matronensis, 
d’Orbigny,’ but apparently somewhat longer. 
I am unable to distinguish M. obesa, Keeping (from Upware), from M. xqualis ; 
its somewhat greater inflation is, I think, due to crushing. 
Types.—In the British Museum—internal casts from the Sandgate Beds of 
Parham Park. The type of MW. obesa, Keeping, is in the Woodwardian Museum. 
Distribution.— Perna-bed, Crackers, and Beds 35 and 36 (Fitton) of Atherfield. 
Perna-bed of Redchff. Ferrugimous Sands of Shanklin. Atherfield Beds of Seven- 
oaks and Peasmarsh. Hythe Beds of Maidstone. Sandgate Beds of Parham Park. 
Lower Greensand of Upware. 
Moprora reveErRsA, Sowerby, 1836. Plate XV, figs. 15, 16, 17 a, b, 18 a 
Plate XVI, figs. 1, 2.a, b, 3. 
C5 
1836. Moprona reversa, J. de C. Sowerby. Trans. Geol. Soc., ser. 2, vol. iv, 
pp. 241, 342, pl. xvii, fig. 13. 
? 1842. — L&HVIGATA, H. B. Geinitz. Char. der Schicht. und Petref. des 
siichs.-béhm. Kreidegeb., pt. 3, p. 78, pl. xx, fig. 35. 
? 1843. = REVERSA, H. B. Geinitz. Die Verstei. von Kieslingswalda, p. 15, 
pl. ii, fig. 11. 
1844, Myrrnus semirapiatus, A. d’Orbigny. Pal. Frane. Terr. Crét., vol. ii, 
p. 277, pl. ccexlhi, figs. 1, 2. 
1850. Moprona reversa, H. B. Geinitz. Das Quadersandst. oder Kreidegeb. in 
Deutschland, p. 168 (partim). 
1850. Mrrytus reversus, A. d’Orbiyny. Prodr. de Pal., vol. 11, p. 165. 
1854. Moprona reversa, J. Morris. Cat. Brit. Foss., ed. 2, p. 211. 
1867. Myrinus (Mopiota) reversvs, F. J. Pictet and G. Campiche. Foss. Terr. 
Crét. Ste. Croix (Matér. Pal. Suisse, ser. 4), p. 510. 
1868. — rEVERSUS, A. Briart and F. L. Cornet. Descript. Min. géol. et 
Pal. de la Meule de Bracquegnies (Mém. cour. et 
Mém. des Sav. étrangers, vol. xxxiv), p. 53, pl. iv, 
figs. 9, 10. 
1 «Boss. Terr. Crét. Ste. Croix” (‘ Mater. Pal. Suisse,’ ser. 3, 1866), pp. 517, 524, pl. exxxiv 
tig. 8. 
2 «Zeitschr. d. deutsch. geol. Gesellsch.,’ vol. xlviii (1896), p. 843, pl. xxi, f. 4; and ‘Die Biv. u, 
Gastrop. d. deutsch. u. hollind. Neoc.’ (1900), p. 65. 
8 «Pal. Franc. Terr, Crét., vol. ii (1844), p. 269, pl. ccexxxvil, figs. 14—16. 
