FOKAMINIFERA OF THE NORTH PACIFIC OCEAN. 67 



and convex below to convex above and flattened below; all chambers 

 visible from the dorsal side, only those of the last-formed coil visible 

 from below; the umbilical region as usually filled with clear shell 

 material; surface variously ornamented with raised bosses or costse or 

 smooth and unornamented ; aperture a single curved opening toward 

 the periphery on the ventral side of the chamber. 



There are several species of this genus presenting a considerable 

 range of form and ornamentation. Certain of the species are abund- 

 ant in shallow water of the temperate or even subarctic zones, while 

 others are characteristic of shallow waters of the tropics. The largest 

 and most ornate species are these latter. 



ROTALIA BECCARn (Linnaeus). 

 Plate 30, fig. 3. 



"Cornu Hammonis" Plancus, Conch. Min., 1739, p. 8, pi. 1, fig. 1 A-c. 



"Ammonia unita" Gaultieri, Index Test., 1742, pi. 19, figs, h, i. 



Nautilus beccarii Linn.eus, Syst. Nat., ed. 12, 1767, p. 1162; ed. 13 (Gmelin's), 



1788, p. 3370, No. 4. 



"Hammoniae conico-tuberculacae " Soldani, Testaceographia, vol. 1, pt. 1, 



1789, p. 56, pi. 35, fig. P. 



Rotalia (Turbinulina) beccarii d'Orbigny, Ann. Sci. Nat., vol. 7, 1826, p. 275, 

 No. 40; Modeles, No. 74. — Parker, Jones, and H. B. Brady, Ann. Mag. 

 Nat. Hist., ser. 3, vol. 16, 1865, p. 30, pi. 3, fig. 83. 



Rotalia beccarii Parker and Jones, Philos. Trans., vol. 155, 1865, p. 388, pi. 16, 

 figs. 29, 30.— H. B. Brady, Ann. Mag. Nat. Hist., ser. 4, vol. 6, 1870, p. 303, 

 pi. 12, figs. 8a-c. — Schwager, Boll. com. geol. Ital., vol. 8, 1877, p. 26, pi., 

 fig. 43.— Terrigi, Atti Accad. Pont. Nuovi Lincei, vol. 33, 1880, p. 208, 

 pi. 3, fig. 62, pi. 4, fig. 63-66.— H. B. Brady, Rep. Voy. Challenger, Zoology, 

 vol. 9, 1884, p. 704, pi. 107, figs. 2, 3.— Wright, Proc. Belfast Nat. Field 

 Club, 1884-85, App. 9, 1886, p. 332, pi. 27, fig. 15.— Malagoli, Boll. Soc. geol. 

 Ital., vol. 6, 1887, p. 523, pi. 13, fig. 11.— Terrigi, Mem. Accad. Lincei, ser. 

 4, vol. 6, 1889, p. 119, pi. 9, figs. 4, 5. — Egger, Abh. kon. bay. Akad. Wise. 

 Munchen, CI. u, vol. 18, 1893, p. 420, pi. 19, figs. 25-27.— Goes, Kongl. 

 Svensk. Vet. Akad. Handl., vol. 25, No. 9, 1894, p. 99, pi. 16, fig. 811.— 

 Rhumbler, Zeitschr. Wiss. Zool., vol. 57, 1894, p. 574, pi. 22, fig. 41.— Lis- 

 ter, Philos. Trans., vol. 186, 1895, p. 436, pi. 8, figs. 38-40.— Fornasini, Mem. 

 Accad. Sci. Inst. Bologna, 1898, p. 259, figs.— Flint, Rep. U. S. Nat. Mus., 

 1897 (1899), p. 331, pi. 75, fig. 2.— Wright, Geol. Mag., dec. 4, vol. 7, 1900, 

 p. 100, pi. 5, fig. 22. — Fornasini, Mem. Accad. Sci. Inst. Bologna, ser. 5, 

 vol. 10, 1902, p. 59, figs. 56-58.— Millett, Journ. Roy. Micr. Soc, 1904, 

 p. 502.— Chapman, Journ. Quekett Micr. Club, ser. 2, vol. 10, 1907, p. 139 — 

 Cushman, Proc. Boston Soc. Nat. Hist., vol. 34, 1908, p. 31. — Sidebottom, 

 Mem. and Proc. Manchester Lit. and Philos. Soc, vol. 53, No. 21, 1909, 

 p. 10, pi. 4, fig. 6; vol. 54, No. 16, 1910, p. 28. 



Description. — Test with the sides about equally biconvex; cham- 

 bers numerous, from 8-12 in the last formed whorl; peripheral 

 margin rounded; sutures limbate above, oblique, ventrally much 

 depressed; the sides beaded or irregularly ornamented; umbilical 

 region often filled with a rounded mass of material about which is a 



