12 



BULLETIN 104, UNITED STATES NATIONAL MUSEUM 

 Nonion labradoricum — Material examined 



NONION ORBICULARE ( H. B. Brady) 



Plate 5, figures 1-3 



Nonionina orbicularis H. B. Brady, Ann. Mag. Nat. Hist., ser. 5, vol. 8, 

 1881, p. 415, pi. 21, figs. 5 a, b; Denkschr. Kais. Akad. Wiss. Math-Nat. 

 CI., vol. 43, 1881, p. 17, pi. 2, figs. 5 a, b; Rep. Voy. Challenger, Zoology, 

 vol. 9, 1884, p. 727, pi. 109, figs. 20, 21.— Heron-Allen and Earland, 

 Trans. Linn. Soc. London, ser. 2, vol. 11, 1916, p. 280. — Cushman, 

 Contr. Canadian Biol., 1921 (1922), p. 13. 



Test planispiral, *bilaterally symmetrical, completely involute, 

 periphery very broadly rounded; chambers 10 to 12 in the last- 

 formed coil, distinct, not inflated, of uniform shape; sutures distinct, 

 slightly depressed, slightly limbate toward the proximal end; wall 

 very finely perforate, smooth; aperture, a long, very narrow slit at 

 the base of the apertural face, sometimes divided into several openings. 



Diameter, 0.75 mm.; thickness, 0.50 mm. 



This species described from the Arctic off Nova Zembla has occurred 

 typically in Hudson Bay, and is recorded by Heron-Allen and Ear- 

 land off the west coast of Scotland. Brady in the Challenger Report 

 gives the following localities : West coast of Nova Zembla, 55 fathoms; 

 shores of Spitzbergen, 7 fathoms; Faroe Channel, 632 fathoms; 

 west coast of Scotland, 25 fathoms, and off Valentia, 112 fathoms. 

 He also records it fossil from a Post-Tertiary clay on the coast of 

 Fifeshire. 



The forms recorded from warm waters and referred to this species 

 are not the same. 



