420 CRETACEOUS LAMELLIBRANCHIA. 



? 1866. OsTREA (Exooyra) 8p. cfr. siomoidea, K. A. Zittel. Bivalv. d. Gosaugeb. 



(Denkschr. d. k. Akad. Wissensch. 

 Wien, Math.-nat. CI., vol. xxxv, 

 pt. 2), p. 123, pi. xix, fig. 5. 

 1869. — SIOMOIDEA, H. Coqnand. Mon. Ostrea, Terr. Crt't., p. 93, pi. xxxiv. 



figs. 5 — 7 bis. 

 1872. — (Exooyra) siomoidea, H. B. Geinitz. Das Elbthalgeb. in Sachsen 



(Palaeontogniphica, vol. 

 XX, pt. 1), p. 186, pi. xli, 

 figs. 14—27. 

 ? 1882. Exooyra cfr. siomoidea, B. WiiidnuJller. Jahrb. d. k. preuss. geol. 



Laudesanst. fiir 1881, 

 p. 30. 

 1888. — siomoidea, G. Midler. Ibid, fiir 1887, p. 401. 



1911. — — A. Fritsch. Stud, im Geb. d. biilimisch. Kreidef., 



Korycaner Schicht., p. 46, fig. 209. 



Remarls. — The only English specimen I have seen is a right valve collected by 

 Mr. LI. Treacher. The strong carina, the concentric ribs on the anterior slope, 

 the more sinuous and more oblique posterior margin and growth-lines distinguish 

 this species from the Rauliniana form of E. ronlca. The inner margin of the 

 valve is finely crenulate. The types came from the Lower Planer-kalk of Schilling 

 near Bilin. 



Distribution. — Zone of Micraster cor-ang iiinum of Boxford, Berkshire.^ 



Family— UABIOLITIBJE, Gmij. 

 [Omitted from Vol. II, p. 210.] 



Genus — Dukania, H. Douville, 1908. 



■(' Bull. Soc. gcol. de France,' ser. 4, vol. viii, p. 309, and ' Mi'm. Soc. geol. de France, Palt'out.,' vol. 



xviii, 1910, p. 23.) 



DuRANiA MoiiTONi (Mantell), 1833. 



1833. HiPPDBiTES MoRTONi, G. Mantell. Geol. S.E. England, p. 130. 

 1836. CoNiA, R. Hudson. Loudon's Mag. Nat. Hist., vol. ix, p. 104, fig. 19. 

 1838. Sph^rulites Mortoni, /. E. Gi-ay. Mag. Zool. Bot., vol. ii, p. 228. 

 1850. Hippurites Moetoni, /. de C. Sotverhy, in F. Dixon. Geol. Sussex, p. 354 



(p. 386, ed. 2), pi. 



xxvi, figs. 1, 2, 4. 



1 White and Treacher, 'Quart. Journ. Geol. Soc.,' vol. Ixii (1906), p. 618. 



