CARDIOMORPHA OBLONGA. 259 



I am unable to agree with de Koninck that shells with edentulous hinges 

 should be placed under Pachydomus of Morris ; and retain the species described 

 under this generic name as Cardiomoiyha, although they have not the markedly 

 enrolled umbones of the type of this genus, and at the same time are more 

 orbicular, and have a thicker shell and more marked concentric striations. These 

 characters, however, are not absolutely peculiar to the shells included under 

 Pachydomus by de Koninck, for C. corrugata and C. orbicularis have an orbicular 

 outline. 



Hall has erected a genus Euthydesma on a single species (' Pal. New York,' 

 vol. v, pt. 2, p. 32) which he places near Cardiomorpha, and which has somewhat 

 the appearance of these shells, but at present I prefer including them in the 

 genus Cardiomorpha. 



Caediomoepha oblonga, Soiverby, sp., 1825. Plate XXI, figs. 1 — 6. 



Isocabdia oblonga, J. de C. Soicerby, 1825. Min. Conch., vol. v, p. 148, 



pi. ccccxci, fig. 2. 



— — Fleming, 1828. Hist. Brit. Anim., p. 420. 



— — Woodward, 1830. Synops. Table Brit. Org. Eem., p. 13. 



— — Deshayes, 1S35. Hist. Nat. Anim. sans Vert., 2nd edit., 



t. vi, p. 450. 



— — Phillips, 1836. Geol. Torks., pt. 2, p. 209, pi. v, fig. 9. 

 Non Cabdiomobpha oblonga, de Koninck, 1S42. Desc. des anim. foss. de la Belgique, 



p. 105, pi. ii, fig. 7. 



— — Morris, 1843. Cat. Brit. Foss., p. 81. 



— — M'Coy, 1844. Syn. Carb. Limest. Foss. Ireland, p. 56. 



— — Bronn, 1848. Nomencl. pala?ont., p. 223. 



— — Brown, 1849. Illus. Foss. Conch., p. 197, pi. lxxix, 



figs. 30, 31 ; pi. lxxxi, fig. 8. 

 _ _ d'Orligny, 1852. Prodrome de Pal., p. 132. 



— — de EycMolt, 1852. Melange pal., p. 102. 



_ ? _ s. P. Woodward, 1854. Man. Mollusca, p. 323. 



— — Morris, 1854. Cat. Brit. Foss., 2nd edit., p. 191. 



— — IP Coy, 1855. Brit. Pal. Foss., p. 510. 



Non — — Young and Armstrong, 1871. Trans. Geol. Soc. Glasg., 



vol. iii, Appendix, p. 50. 



— — Baihj, 1871. Figures Char. Brit. Foss., vol. i, p. 115, 



pi. xxxix, fig. 10. 



— — Young and Armstrong, 1876. Catal. Foss. "W. Scot., p. 53. 



— — Rbmer, 1876. Lethsea Pal., pi. xliv, fig. 5. 



— — Bigsby, 1878. Thesaurus Devonico-carb., p. 301. 



— — de Koninck, 1S85. Ann. Mus. Roy. Hist. Nat. Belgique, 



vol. xi, p. 11, pi. ii, figs. 3, 4 ; pi. 

 iii, figs. 10, 11. 



— QX7ADEATA, de Koninck, 1885. Ibid., p. 13, pi. iii, figs. 



