14 



BULLETIN 11, UNITED STATES NATIONAL MUSEUM. 



rather broad; sutures slightly curved, either depressed or limbate 

 with clear shell material as is also the peripheral margin; dorsally 

 rather coarsely perforate, and also ventrally, 

 umbilical region either wide open or closed 

 by a stellate callouslike thickening of clear 

 material; aperture a rather large opening, 

 elongate, often with a valvular umbilical end. 



Diameter 0.40-1 mm. 



Distribution. — Flint records D. rosacea from 

 a single station in the North Pacific, "coast 

 of Alaska, station unknown." I have had a 

 few typical specimens from Albatross station 

 D2932 in 20 fathoms. 



DISCORBIS VILARDEBOANA (d'Orbigny). 



Plate 9, fig. 2. 



Rosalind vilardeboana d'Orbigny, Voy . Amer. Merid., 

 1839, "Foraminiferes," p. 44, pi. 6, figs. 13-15. 

 Discorbina vilardeboana Parker and Jones, Quart. 

 Journ. Geol. Soc, vol. 28, 1872, p. 115.— H. B. 

 Brady, Rep. Voy. Challenger, Zoology, vol. 9, 

 1884, p. 645, pi. 86, figs. 9, 12; pi. 88, fig. 2.— 

 Egger, Abh. kon. bay. Akad. Wiss. Munchen, 

 CI. n, vol. 18, 1893, p. 387, pi. 15, figs. 13-15.— 

 Goes, Kongl. Svensk. Vet. Akad. Handl., vol. 

 25, No. 9, 1894, p. 95, pi. 16, fig. 796.— Chapman, Journ. 

 Roy. Micr. Soc, 1898, p. 15, pi. 2, fig. 16.— Millett, 

 Journ. Roy. Micr. Soc, 1903, p. 699. — Rhumbler, Zool. 

 Jahrb., Abt. Syst., vol. 24, 1906, p. 68.— Bagg, Proc U. S. 

 Nat. Mus., vol. 34, 1908, p. 157. — Sidebottom, Mem. and 

 Proc. Manchester Lit. and Philos. Soc, vol. 52, No. 13, 

 1908, p. 12; vol. 54, No. 16, 1910, p. 25.— Bagg, Bull. 

 U. S. Geol. Surv., No. 513, 1912, p. 82, pi. 28, fig. 9a-c. 



Description. — Test plano-convex, dorsal side rather 

 evenly rounded, ventral side flattened or slightly con- 

 cave; peripheral margin rounded ; chambers five to seven 

 in the last-formed whorl, the last-formed one, especially 

 on the ventral side, often occupying nearly one-third 

 of the ventral surface; sutures clear, slightly depressed, 

 more so on the ventral side, which is often slightly um- 

 bilicate; wall finely punctate; aperture an arched slit 

 running from the umbilicus nearly to the peripheral Fig14 -- Discorbisvi - 



. , , - „ • l • 1 LARDEBOANA (D'Or- 



margin; early chambers olten brownish in color. bigny). (adapted 



FROM D'ORBIGNT'S 

 FIGURE OF THE TYPE.) 



a, dorsal view; b, 

 side view; c, ven- 

 tral VIEW. 



Fig. 13. — Discorbis rosacea 

 (d'Orbigny). x 100. o. dor- 

 sal view; 6, side view; c, ven- 

 tral view. (Adapted from 

 Brady.) 



Diameter 0.40-0.60 mm 



Distribution. — Brady records this species with D. 

 auracana from the shores of Japan. Bagg had it from 

 two Albatross stations in the vicinity of the Hawaiian 

 Islands, H4440 in 1,259 fathoms and H4568 in 1,274 fathoms 

 bier records it from Laysan Island. 



Rhum- 



