MARGINULINA COSTATA. 237 



NoDOSARiA SEMEN, Boderleiu, =. Maeginulina eaphanus, Malagoli, 1888. Atti 



Accad. Modena, ser. 

 3, vol. vii, fasc. 1, 

 p. 2, pi. i, figs. 1, 2. 

 Maeginflina COSTATA, Sherhom and Chapman, 1889. Journ. R. Micr. Soc. for 



1889, p. 487, pi. xi, 

 fig. 28. 



— Pecketi, Sclirodt, 1890. Zeitsch. Deutsch. Geol. Ges,, vol. xlii, 



p. 409, pi. xxi, fig. 1. 



— COSTATA, Egger, 1893. Abhandl. k. Bayer. Akad. Wiss., vol. xviii, 



part 2, p. 347, pi. xi, fig. 19. 



— — Fornasini, 1893. Mem. R. Accad. Sci. Istit. Bologna, 



ser. 5, vol. iii, p. 434, pi. ii, fig. 6 ; 

 vol. iv, 1894, pp. 213, 214, 217, 

 pi. ii, figs. 19 — 21. (Nodosaria and 

 Marginulina cultrata, and Nod. con- 

 stricta, Costa.) 

 NoDOSAEiA EAPHANUS, Dervieux, 1894. Boll. Soc. Geol. Ital., vol. v, fasc. 4, 



p. 621, pi. V, figs. 56—59. 

 Maeginulina ^quivoca (Rss.), Chapman, 1894. Journ. E. Microsc. Journ. for 



1894, p. 162, pi. iv, fig. 20. 

 (Eccentric Nodosaria ra- 

 phanus.} 



— MuNiEEi (Berth.), Idem, 1894. Ibid., p. 163, pi. iv, fig. 22. 



— EOBUSTA (Rss.), Idem., 1894. Ibid., p. 163, pi. iv, fig. 23. 



— JoNESi (Rss.), 7c?eOT, 1894. Ibid., p. 163, pi. iv, fig. 24. 

 NoDOSAEiA MAEGiNULiNoiDES, Fomasini, 1895. Mem. R. Accad. Sci. Istit. 



Bologna, ser. 5, vol. v, p. 10, 

 pi. iv, fig. 7. (A passage- 

 form.) 

 Ceistellaeia SULCATA, Fomastni, 1895. Ibid., p. 11, pi. iv, figs. 26, 27. (= Cr. 



sulcata, Costa; M. costata, with few 

 ribs.) 

 Maeginulina costata. Be Amicis, 1895. IS'at. Sicil., vol. xiv, pp.35 and 61. 



Characters. — This Nodosarine is essentially a Nodosaria having an eccentric 

 growth, which gives either an oblique or partially spiral style of growth to the 

 early chambers, and a marginal aperture (with or without a short neck) to the 

 older and the last segments. It varies in cross-section from subcylindrical to oval 

 and compressed. The chambers are moderately compact ; more or less septate, 

 and therefore varying in relative fulness ; and are marked with longitudinal 

 riblets, as in Nodosaria raphanus, of which, indeed, this is essentially only a 

 Marginuline modification. 



Occurrence. — Marginulina costata seems to be most at home in the North and 

 South Atlantic, the Mediterranean, and the Adriatic (370 — 1240 fathoms) ; but 



