FOEAMINIFERA OF THE NORTH PACIFIC OCEAN. 



13 



DISCORBIS OBTUSA (d'Orbigny). 



Rosalina obtusa d'Orbigny, For. Foss. Bass. Tert. Vienne, 1846, p. 179, pi. 11, 



figs. 4-6. 

 Discorbina obtusa H. B. Brady, Rep. Voy. Challenger, Zool- 

 ogy, vol. 9, 1884, p. 644, pi. 91, fig. 9a-c— Bagg, Proc. 



U. S. Nat. Mus., vol. 34, 1908, p. 156. 

 Discorbina (Rosalina) obtusa Egger, Abh. kon. bay. Akad. 



Wiss. Munchen, CI. n, vol. 18, 1893, p. 391, pi. 15, figs. 



67-69. 

 Discorbina turbo, var. vesicularis, subvar. obtusa Parker 



and Jones, Philos. Trans., vol. 155, 1865, p. 386, pi. 14, 



figs. 18, 19. 



Description. — Test biconvex, dorsal side slightly 

 more so than the ventral side; peripheral margin 

 rounded; chambers comparatively few, about five in 

 the last-formed whorl; sutures curved, depressed; 

 surface with numerous perforations; aperture an 

 elongate narrow slit extending from the umbilicus 

 nearly to the periphery on the ventral border of the 

 chamber. 



Diameter up to 1 mm. 



Distribution. — Bagg records this species from Al- 

 batross station H4568 in 1,274 fathoms off the Ha- 

 waiian Islands. This seems to be the only North 

 Pacific record for this species. 



Fig. 12. — Discorbis 

 obtusa (d'Orbigny). 

 (Adapted from 

 d'Orbignt's origi- 

 nal FIGURE.) a, DOR- 

 SAL view; b, side 



VIEW; C, VENTRAL 

 VIEW. 



DISCORBIS ROSACEA (d'Orbigny). 



Rotalia rosacea d'Orbigny, Ann. Sci. Nat., vol. 7, 1826, p. 273, No. 15; Modeles, 

 No. 39. 



Asterigerina rosacea d'Orbigny, Prod. Pal., vol. 3, 1852, p. 158, No. 2952. 



Discorbina rosacea II. B. Brady, Trans. Linn. Soc, vol. 24, 1864, p. 473, No. 

 69. — Parker, Jones, and H. B. Brady, Ann. Mag. Nat. Hist., ser. 3, vol. 

 16, 1865, p. 25, pi. 2, fig. 71— Parker, Jones, and H. B. Brady, Pal. Soc. 

 Monograph 19, 1866, pi. 4, fig. 17.— Goes, Kongl. Svensk. Vet. Akad. Handl., 

 vol. 19, pt. 4, 1882, p. 105, pi. 8, figs. 251-257.— H. B. Brady, Rep. Voy. 

 Challenger, Zoology, vol. 9, 1884, p. 644, pi. 87, figs. 1, 4.— Sherborn and 

 Chapman, Journ. Roy. Micr. Soc, 1886, p. 756, pi. 16, fig. 11.— Egger, 

 Abh. kon. bay. Akad. Wiss. Miinchen, CI. n, vol. 18, 1893, p. 385, pi. 15, 

 figs. 39-41.— Goes, Kongl. Svensk. Vet. Akad. Handl., vol. 25, No. 9, 1894, 

 p. 94, pi. 15, fig. 792.— Flint, Rep. U. S. Nat. Mus., 1897 (1899), p. 327, 

 pi. 72, fig. 3.— Millet, Journ. Roy. Micr. Soc, 1903, p. 698.— Chapman, 

 Journ. Quekett Micr. Club, ser. 2, vol. 10, 1907, p. 135.— Cushman, Proc. 

 Boston Soc. Nat. Hist., vol. 34, 1908, p. 30. — Sidebottom, Mem. and Proc. 

 Manchester Lit. and Philos. Soc, vol. 52, No. 13, 1908, p. 12, pi. 4, figs. 

 3-5; vol. 54, No. 16, 1910, p. 25. 



Discorbina turbo, var. rosacea Parker and Jones, Philos. Trans., vol. 155, 1865, 

 p. 385, pi. 16, fig. 28a, b. 



Description. — Test plano-convex, dorsal side conically convex, ven- 

 tral side flat or somewhat concave; peripheral margin acute, cari- 

 nate; chambers numerous, six or seven in the last- formed whorl, 



