76 BULLETIN 104, UNITED STATES NATIONAL MUSEUM. 



Description. — Test small, thin, much compressed, trochoid, con- 

 sisting of about two volutions; chambers about eight in the last- 

 formed coil, sutures not depressed, evenly curved, those of the 

 ventral side, slightly angled ; wall finely arenaceous, almost translu- 

 cent; aperture a narrow slit near the inner margin of the chamber; 

 color yellowish brown. 



Diameter, 0.25 mm. 



Distribution. — Williamson's type material was from the Shetlands. 

 It is knoAvn from other localities from about the British Isles, 

 especially off Ireland aud Scotland. I have seen no specimens of 

 this species in the Albatross or other material that I have examined. 



TROCHAMMINA PLICATA (Terquem). 



Plate 15, fig. 4. 



Patelliaa plicata Terquem, Ess. Anim. Plage Dunker(|ue, pt. 2, 187G, p. 72, pi. 8, 

 figs. 9, a, b. 



Trochammina plicata Balkwill and Wright, Journ. Micr., vol. 3, 1884, p. 26, 

 pi. 1, fig. 8. — Halkyard, Trans. Ann. Rept. Manchester Micr. Soc, 1889, 

 p. 69, pi. 1, fig. 11. — J. Wright, Proc. Roy. Irish Acad., ser. 3, vol. 1, 1891. 

 p. 469.— MiLXETT, Journ. Roy. Micr. Soc, 1899, p. 363, pi. 5, fig. 18.— Heron- 

 Allen and Earland, Proc. Roy. Irish Acad., vol. 31, pt. 64, 1913, p. 51; 

 Trans. Zool. Soc. London, vol. 20, 1915, p. 619; Trans. Linn. Soc. London, 

 vol. 11, pt. 13, 1916, p. 227. 



This species has not occurred so far as I have seen in the Albatross 

 or other American material. It is knouai from the vicinity of the 

 British Isles off both Ireland and Scotland. 



TROCHAMMINA BRADYI Robertson. 



Plate 15, fig. 5. 



Trochammina robertsoni H. B. Brady, Journ. Roy. Micr. Soc, 1887, p. 893. — 

 J. Wright, Proc. Roy. Irish Acad., ser. 3, vol. 1, 1891, p. 469, pi. 20, figs. 

 4a, 6.— Goes, Kongl. Svensk. Vet. Akad., vol. 25, No. 9, 1894, p. 30, pi. C, 

 figs. 231-234.— Earland, Journ. Quekett Micr. Club, ser. ,2, vol. 9, 1905, 

 p. 203. — Heron-Allen and Earland, Proc Roy. Irish Acad., vol. 31, pt. 

 64, 1913, p. 53; Trans. Linn. Soc, London, vol. 11, pt. 13, 1916, p. 228. 



Trochammina bradyi Robertson, Ann. Mag. Nat. Hist., ser. 6, vol. 7, 1891, 

 p. 388. 



Description. — Test small, coiled, very low spired or planospiral, 

 outer whorl consisting of about six chambers, those of the previous 

 whorl slightly exposed in the umbilical region; chambers inflated, 

 subspherical, sutures distinct and depressed; wall fuiely arenaceous, 

 with much cement, smooth; aperture a narrow crescentiform slit at 

 the base of the apertural face of the chamber; color yellowish brown. 



Diameter, about 0.25 mm. 



Distribution. — This species seems to be common in the waters of 

 the British Isles, but has not so far been recorded from the western 

 Atlantic. 



