246 FORAMINIFERA OF THE CRAG. 



Cristellaeia culteata, Idem, 1892. Boll. Soc. Geol. Ital., vol. x, p. 582. 



— — Malagoli, 1892. Ibid., vol. xi, p. 95. 



— * — Hosius, 1892. Verhandl. nat. Ver. preuss. Eheinland, 



49 Jahrg., p. 189. 



— — Crick and Sheriorn, 1892. Journ. Northamptonshire 



Nat. Hist. Soc, vol. vii, p. 70, pi. vii, 

 fig. 13. 



— EOTTJLATA, Efff/er, 1893. Abhandl. Bayer. Akad. "Wiss., vol. xviii, 



p. 351, pi. xii, fig. 2 (not quite keelless). 



— CTJLTRATA, Idem. Ibid., fi-gs. 7 — 10, 24, 25. 



— — De Amieis, 1893. Boll. Soc. Geol. Ital., vol. xii, fasc. 3, 



p. 417 (synonyms). 



— — Fornasini, 1894. Mem. E. Accad. Sci. Istit. Bologna, 



ser. 5, vol. iv, pp. 221, 222, pi. iii, 

 figs. 26, 27 ; vol. v, 1895, p. 12, 

 pi. iv, fig. 31 (fig. 27 = Cr. festo- 

 nata, Costa). 



— EOXULATA (including culteata), Goes, 1894. K. Svensk. Vet.- 



Ak. Handl., vol. xxv, No. 9, p. 59, pi. x, 

 figs. 559—578. 



— ctFLTEATA, De Amicis, 1895. Nat. Sieil., Ann. xiv, pp. 43 and 62. 



— EOTULATA, logger, 1895. Jahresb. Naturhist. Ver. Passau, p. 26, 



pi. iii, figs. 4, 7. 



]>^OTB. — The synonymy of Gristellaria cultrata and its very numerous allies is 

 dealt with in the " Remarks on the Foraminifera with especial reference to their 

 Variability of Form, illustrated by the Cristellarians," by Prof. T. Rupert Jones, in 

 the 'Monthly Microsc. Journ.,' vol. xv, 1876, pp. 61—92, and pp. 20, 201. At 

 pp. ^l — 84 the synonymy of the varietal modifications of Gristellaria calcar, 

 whether keelless or keeled, rowelled, outspread, trihedral, or elongate, is detailed, 

 as indicated by published forms, from 1735 to 1846. The second part (by T. R. 

 Jones and C. D. Sherborn) of the same memoir appeared in the ' Journ. Roy. 

 Microsc. Society,' vol. for 1887, part 2, j^p. 645 — 557. The selection for the 

 synonymy is chiefly guided by the absence of ornament and of any peculiarity in 

 the shape of the chambers, and doubtless is merely an ai'tificial arrangement of 

 the forms lying between G. rotidata and G. cassis. 



Gharacters. — Shell lenticular, nautiloid, smooth, consisting of one or more 

 spiral whorls of subtriangular or falciform chambers, the outermost embracing 

 the inner whorls. Septal sutures variable in expression; sometimes sunken, 

 often limbate. Umbones sometimes much thickened. Margin keeled ; carina 

 narrow or wide. Aperture round or angular. 



Diameter of specimens from the Crag about one-twentieth of an inch (1| mm.) ; 

 but some from other sources attain very much larger dimensions. 



Occurrence. — Cristellaria cidtrata is found in various fossiliferous strata, com- 



