OPERCULINA COMPLANATA. 363 



Opebctjlina complanata, Parher and Jones, 1863. Ann. Nat. Hist., ser. 3, 



vol. xii, p. 207, No. 36 ; p. 435, No. 36 ; 

 and p. 440, No. 15. 



— — Parker, Jones, and Brady, 1865. Ibid., vol. xvi, p. 32, 



pi. iii, fig. 93. 



— — Jones, Parker, and Brady, 1866. Monogr. For. Cra^, 



Append, i and ii, Tables, Nos. 93, 94, 

 pi. ii, figs. 49, 50. 



— Studebi, Kaufmann, 1867. Geol. Beschreib. Pilatus, p. 151, pi. ix, 



figs. 1, 2. 



— maeginata, Kaufmann, 1867. Ibid., p. 152, pi. ix, fig. 4. 



— COMPLANATA, Zittel, 1876. Handb. Pal., vol. i, p. 96, fig. 36. 



— — Schwager, 1877. Boll. it. Com. Geol. Ital., vol. viii, 



p. 25, fig. 22. 



— — Locard, 1877. Ann. Agric. Lyon, ser. 4, vol. ix, p. 231, 



pi. v, figs. 6, 7. 



— — Jones, 1882. Catal. Foss. Foram. Brit. Mus., pp. 22, 



36, 40, 53, 69, 73, 80, 94. 



— — Mobius, 1880. Foram. Mauritius, p. 104. 



— Arabica, Jones, 1883. Microgr. Diet., p. 555, pi. xxiv, figs. 23—26. 



— complanata, Brady, 1884. ' Challenger ' Report, p. 743, pi. cxii, 



figs. 3—5, 8. 



— Basset, 1885. Ann. Soc. Sci. Nat. Charente-Inf., 



No. 21, p. 162, fig. 80. 



— — Woodward and Thomas, 18S5. Thirteenth Rep. Geol. 



Surv. Minnesota, p. 175, pi. iv, fig. 35. 



— — Gumbel, 1885. Geol. Bayer., vol. i, part 2, p. 421, 



fig. 266 28 . 



— — Bgger, 1893. Abhandl. k. Bayer. Akad. AViss., vol. 



xviii, p. 435, pi. xx, figs. 40 — 42. 



— — Be Amicis, 1893. Boll. Soc. Geol. Ital., vol. xii, p. 464. 



— — Woodward and Thomas, 1895. Final Report Geol. 



Surv. Minnesota, vol. iii, part 1, p. 45, 

 pi. E, figs. 37 and 39. 

 — Chapman, 1895. Proc Zool. Soc. for 1895, p. 47. 



Characters. — Shell discoidal, complanate, subumbonate ; consisting of three 

 or four revolutions, rapidly increasing in breadth ; chambers numerous, radial or 

 arcuate; septa subtranslucent, sometimes limbate. 



Distribution. — Operculina complanata is essentially a shallow-water form, and 

 is confined to tropical and subtropical seas. No specimens have been obtained 

 from the Atlantic. 0. ammonoides represents it in the North Atlantic. 



Fossil in the Chalk of Maestrichtand Minnesota ; in the Eocene of Central 

 Europe and India; in the Miocene of Italy and of Muddy Creek (Victoria); 

 and in great profusion in the Langhian of the Bordeaux area. So far as the 



47 



