24 BULLETIN 161, UNITED STATES NATIONAL MUSEUM 



the genus Oridorsalis. The genus Oridorsalis is separated from 

 Pseudoeponides in lacking the ventral accessory apertures. Andersen 

 (1961, p. 107-109) leaves open the question of relationship between 

 Reuss' Oligocene species Rotalina umbonata and the genus Oridorsalis. 

 Assuming the assignment of umbonata to Oridorsalis can be confirmed, 

 it is likely that Oridorsalis westi Andersen (the type species of Oridor- 

 salis) will fall into synonymy with Oridorsalis umbonatus. 



This long-ranging and cosmopolitan deep-water species occurs in 

 many of the samples but not more than rarely. Preservation is 

 generally not good and the dorsal apertures are obscured in most of 

 the specimens. As in Gyroidina soldanii, variation in size is con- 

 siderable. The wall is smooth and shiny and usually opaque, and the 

 sutures are indistinct. 



Genus STOMATORBINA Dorreen, 1948 



STOMATORBINA CONCENTRICA (Parker and Jones) 



Plate 16, Figures 1, 2 



Pulvinulina concentrica Parker and Jones, in Brady, 1864, Trans. Linn. Soc. 

 London, vol. 24, p. 470, pi. 48, fig. 14. — Brady, 1884, Rep. Voy. Challenger, 

 Zoology, vol. 9, p. 686, pi. 105, fig. 1. 



Eponides concentrica Cushman, 1931, U.S. Nat. Mus. Bull. 104, pt. 8, p. 43, pi. 

 9, figs. 4, 5. — Chapman, Parr, and Collins, 1934, Journ. Linn. Soc, Zool., 

 vol. 38 (no. 262), p. 565, pi. 9, fig. 17.— Colom, 1942, Instit. Espanol Oceano- 

 grafia, Notas y Resumenes, ser. 2, no. 108, p. 39, pi. 7, figs. 136, 137.- — 

 Parr, 1945, Proc. Roy. Soc. Victoria, vol. 56 (new ser.), pt. 2, p. 213, pi. 

 11, fig. 6. 



Mississippina concentrica (Parker and Jones).- — Said, 1949, Cushman Lab. 

 Foram. Res., Spec. Publ. 26, p. 37, pi. 4, fig. 1.— Uchio, 1952, Trans. Proc. 

 Paleont. Soc. Japan, new ser., no. 7, p. 197, pi. 18, figs. 1, 3-5. — Cushman, 

 Todd, and Post, 1954, U.S. Geol. Surv. Prof. Paper 260-H, p. 360, pi. 89, 

 fig. 27/ — Colom, 1956, Mem. Real Acad. Ciencias Artes Barcelona, vol. 

 32, no. 5, p. 79, pi. 12, figs. 39, 40. 



Stomatorbina concentrica (Parker and Jones). — Phleger and Parker, 1951, 

 Geol. Soc. Amer. Mem. 46, pt. 2, p. 22, pi. 12, fig. 2.— Gianotti, 1953, Riv. 

 Ital. Pal. Stratig., Mem. 6, p. 278, pi. 17, fig. 2. — Kaasschieter, 1955, 

 Verh. Kon. Nederl. Akad. Wetensch., Aid. Natuurk., ser. 1, vol. 21, no. 2, 

 p. 87, pi. 9, fig. 4.— Carter, 1958, Geol. Surv. Victoria, Bull. No. 55, p. 40, 

 pi. 4, figs. 37-39; pi. 7, fig. 75.- — Boltovskoy, 1959, Argentina Serv. Hidro. 

 Naval, Publ. H1005, p. 97, pi. 15, fig. 8. 



This widely recorded and probably cosmopolitan deep-water species 

 is found in four of the present samples, but only rarely. The broad, 

 curved opaque bands on the ventral side, parallel with the periphery, 

 are its chief distinguishing characteristic. 



The genera Stomatorbina and Mississippina are quite similar in 

 appearance but seem to be morphologically distinct. Stomatorbina has 

 broad raised limbate bands marking the dorsal sutures, whereas in 

 Mississippina the dorsal sutures are depressed. In both genera the 



