68 



BULLETIN 71, UNITED STATES NATIONAL MUSEUM. 



depressed area, wall otherwise smooth; aperture a very narrow slit 

 on the ventral margin of the chamber. 



Diameter 0.60-1 mm. 



Distribution. — This species does not seem to have been definitely 

 recorded from the North Pacific. I have it from Cebu, Philippine 

 Islands, collected by Dr.E. A.Mearns, from Albatross H4878 in 84 fath- 

 oms, bottom temperature 51. 9° F., off Japan and D4968 in 253 fathoms, 

 bottom temperature 45.7°, also off Japan. This is essentially a shal- 

 low water species and is probably widely distributed in the region 

 under such conditions but material from shallow water has been very 

 scanty. 



ROTALIA BROECKHIANA Karrer. 



Plate 27, fig. 4; plate 30, fig. 2. 



Rotalia broeckhiana Karrer, in Drasche, Geol. Insel. Luzon, 1878, p. 98, pi. 5, 

 fig. 26.— H. B. Brady, Rep. Voy. Challenger, Zoology, vol. 9, 1884, p. 705, 

 pi. 107, figs. 4a-c. — Egger, Abh. k6n. bay. Akad. Wiss. Munchen, CI. n, 

 vol. 18, 1893, p. 421, pi. 19, figs. 19-21.— Millett, Journ. Roy. Micr. Soc, 

 1904, p. 503.— Chapman, Journ. Linn. Soc., Zoology, vol. 30, 1910, p. 423. 



Description. — Test nearly equally biconvex, nearly circular in side 

 view; chambers 7 or 8 in the final whorl, narrow; sutures slightly 



depressed, a slight 

 channel between the 

 last formed whorl and 

 the previous one dor- 

 sally ; umbilical region 

 filled with clear shell 

 material as are also 

 the sutures ventrally; 

 surface smooth; aper- 

 ture an elongated somewhat arched slit running from near the 

 umbilical region almost to the peripheral margin on the ventral side. 

 Diameter about 0.75 mm. 



Distribution. — Apparently this species has not previously been 

 recorded from the North Pacific. The only station from which I 

 have found it is Nero 1209 in 660 fathoms, blue mud, off Japan. 



ROTALIA ORBICULARIS d'Orbigny. 

 Plate 29, fig. 3. 



Rotalia (Gyroidina) orbicularis d'Orbigny, Ann. Sci. Nat., vol. 7, 1826, p. 278, 

 No. l;Modeles, No. 13. 



Rotalia orbicularis H. B. Brady, Trans. Linn. Soc, London, vol. 24, 1864, p. 470, 

 pi. 48, fig. 16. — Terquem, Mem. Soc. Geol. France, ser. 3, vol. 2, mem. 3, 

 1882, p. 60, pi. 4, figs. 1-3.— H. B. Brady, Rep. Voy. Challenger, Zoology, 

 vol. 9, 1884, p. 706, pi. 107, fig. 5; pi. 115, fig. 6.— Egger, Abh. kon. bay. 

 Akad. Wiss. Munchen, CI. n, vol. 18, 1893, p. 421, pi. 19, figs. 22-24.— Flint, 

 Rep. U. S. Nat. Mus., 1897 (1899), p. 331, pi. 75, fig. 5 — Sidebottom, Mem. 

 and Proc. Manchester Lit. and Philos. Soc, vol. 54, No. 16, 1910, p. 28.— 

 Chapman, Journ. Linn. Soc, Zoology, vol. 30, 1910, p. 424. 



a b C 



Fig. 61. — Rotalia broeckhiana Karrer. X 50. a, dorsal view; 

 6, hide view; c, ventral view. (After Brady.) 



