GONIOMYA. 255 
Affinities—This species is less inequilateral, and the ribs are less extensively 
developed than in G. caudata, Agassiz." 
Remarks.—English examples of this species were identified by Pictet and 
Renevier, who state that the forms referred by Forbes® to Pholadomya Agassiz 
are really specimens of G. Archiact. 
Type.—From the Aptian of the Perte-du-Rhone. 
Distribution.—Lower Greensand (Crackers) of Atherfield.’ 
GontomyA Martieana (d’Orbigny), 1845. Plate XLII, figs. 6, 7. 
1845. PHotapomya Mariunana, A. d’Orbigny. Pal. France. Terr. Crét., vol. iu, 
p. 355, pl. ccelxiv, figs. 1, 2. 
1845. Gonromya Mariieana, L. Agassiz. Etudes. crit. Moll. Foss., Myes, p. xiv. 
1850. PHotapomr1a Mariieana, A. d’Orbigny. Prodr. de Pal., vol. i, p. 157. 
1854. PuHotapomya Mariurana, J. Morris. Cat. Brit. Foss., ed. 2, p. 220. 
1865. — — F. J. Pictet and G. Campiche. Terr. Crét. Ste. 
Croix (Mater. Pal. Suisse, ser. 
4), p. 93 (Goniomya). 
? 1868. PHotapomya Maruueana, A. Briart and F. L. Cornet. Meule de Bracque- 
enies (Mém. cour. et Mém. des 
Sav. ¢trangers, vol. xxxiv), p. 83, 
pl. vi, fig. 12. 
1870. Gontomya Maruirana, F. Stoliczka.  Palzeont. Indica, Cret. Fauna S. 
India, vol. iui, p. 75. 
2? 1885. PHonapomya (Gontomya) MariuEana, F, Notling. Die Fauna d. baltisch. 
Cenoman. (Paleont. Abhandl., 
vol. ii), p. 36, pl. vi, fig. 9. 
Description.—Shell elongate, subquadrate, convex, very inequilateral. Anterior 
part not so high as the posterior part, compressed, with rounded margin. 
Antero-dorsal margin concave. Postero-dorsal margin long, nearly straight, and 
nearly parallel to the shghtly convex ventral margin. Posterior margin truncated, 
oblique, forming a rounded angle with the ventral margin, and an obtuse angle 
with the postero-dorsal margin. Umbones pointed, directed anteriorly. Lunule 
concave, elongate-ovate, limited by a cara. Escutcheon long, deep near the 
umbones, limited by a carma. Between the carina of the escutcheon and a 
rounded ridge extending from the umbo towards the postero-ventral margin the 
shell is concave. 
1 «Etudes crit. Moll. Foss.,’ Myes (1842), p. 22, pl. 10, figs. 1—3, pl. i, fig. 1. Pholadomya 
Agassiz, d’Orbigny, ‘Pal. Franc. Terr. Cret.,’ vol. i, p. 352, pl. ccelxiii, figs. 1, 2; Pictet and 
Campiche, ‘ Foss. Terr. Crét. Ste. Croix’ (‘ Matér. Pal. Suisse,’ ser. 4, 1865), p. 84, pl. evi, figs. 4—6. 
* “Quart. Journ. Geol. Soc.,’ vol. i (1845), p. 239. Morris, ‘ Cat. Brit. Foss.,’ ed. 2 (1854), p. 176. 
> An imperfect specimen of Goniomya from the Tealby Limestone of Claxby is in the Sedgwick 
Museum, Cambridge. 
