GONIOMYA. 255 



Affinities.- — This species is less inequilateral, and the ri])s are less extensively 

 developed than in (J. candata, Agassiz.^ 



Bemarks. — English examples of this species were identified by Pictet and 

 Renevier, who state that the forms referred by Forbes- to Pholaclomya Agassizi 

 are really specimens of G. Atrhiari. 



Type.— From the Aptian of the Perte-du-Rhone. 



DistrihuiicDi. — Lower Greensand (Crackers) of Atherfield.^ 



GoNiOMYA Mailleana {d'Orhi,ju)j), 18-1-5. Plate XLII, figs. 6, 7. 



1845. Pholadomta Mailleana, A. (TOrhiyny. Pal. Frauc. Terr. Cri't., vol. iii, 



p. 355, pi. ceclxiv, figs. 1, 2. 

 1845. GoNioMYA Mailleana, L. Agassiz. Etudes, crit. Moll. Foss., Myes, p. xiv. 

 1850. Pholadomia Mailleana, A. d'Orhigny. Prodr. de Pal., vol. ii, p. 157. 

 1854. Pholadomta Mailleana, /. Morris. Cat. Brit. Foss., ed. 2, p. 220. 

 1865. — —F.J. Pictet and G. Campiche. Terr. Crct. Ste. 



Ci'oix (Mater. Pal. Suisse, ser. 

 4), p. 93 (Goniomya). 

 ? 1868. Pholadomya Mailleana, A. Briart and F. L. Cornet. Meule de Bracque- 



giiies (Mt'm. cour. et Mem. des 

 Sav. ctraugers, vol. xxxiv), p. 83, 

 pi. vi, fig. 12. 

 1870. Goniomya Mailleana, F. Stoliczka. Palieont. ludiea, Cret. Fauua S. 



India, vol. iii, p. 75. 

 ? 1885. Pholadomya (Goniomya) Mailleana, F. NiitUng. Die Fauna d. baltisch. 



Cenomau. (Palteout. Abbandl., 

 vol. ii), p. 36, pi. vi, fig. 9. 



Descripiiuii. — Shell elongate, sub(iuadrate, convex, very ine(juilateral. Anterior 

 part not so high as the posterior part, compressed, with rounded margin. 

 Antero-dorsal margin concave. Postcro-dorsal margin long, nearly straiglit, and 

 nearly parallel to the slightly 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. Lunide 

 concave, elongate-ovate, limited by a carina. Escutcheon long, deep near the 

 umbones, limited by a carina. 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, pi. ih, figs. 1—3, pi. i, fig. 1. Plwlndomya 

 Agassizi, d'Orbigny, 'Pal. Franc. Terr. Cret.,' vol. iii, p. 352, pi. ccclxiii, figs. 1, 2; Pictet and 

 C'ampielie, ' Foss. Terr. Cret. Ste. Croix ' ('Mater. Pal. Suisse,' ser. 4, 1865), p. 84, pi. cvi, figs. 4 — 6. 



2 ' Quart. Jouru. Geol. See.,' 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 iu the Sedgwick 



Museum, Cambridge. 



