^{page 155 note 1} This is the species which was described as Orthoceras longicameratum by Foord (Cat. Foss. Ceph. Brit. Mus., pt. i, 1888, p. 80), but this name being preoccupied Foord altered it to O. nassoviense (ibid., Corrigenda and Addenda, p. xxxi). The species, however, is evidently the same as that for which Giebel had already proposed the name O. commutatum.

^{page 157 note 1} Trans. Geol. Soc. London, ser. II, vol. vi, pt. 2 (1842), p. 351, pi. xxx, figs. 1, la. Referred to Cyrtoceras (Ooceras) flexuosum, Schlotheim, sp., by Foord, A. H.: Cat. Foss. Ceph. Brit. Mus., pt. i (1888), p. 316.Google Scholar

^{page 157 note 2} Proc. Boston Soc. Nat. Hist., vol. xxii (1883), p. 285. See also Holzapfel, E.: Abhandl. d. k. Preuss. geolog. Landesanst., Neue Folge, Heft 16 (1895), pp. 123Google Scholar et seq. Hyatt originally spelt the name Kophinoceras, a spelling adopted by Holzapfel; but in Eastman's translation of Zittel's Textbook of Palæontology (1900) Hyatt spells the name Cophinoceras (p. 522).

^{page 158 note 1} Described and figured as Cyrtoceras (?) bdellaites by Phillips, J., Pal. Foss. Cornwall, Devon, and West Somerset, 1841, p. 117,Google Scholar pl. xlvii, figs. 223a, b, and referred to D'Archiac & De Verneuil's species by Foord, A. H., Cat. Foss. Ceph. Brit. Mus., pt. ii (1891), p. 58.Google Scholar

^{page 158 note 2} Abhandl. d. k. Preuss. geolog. Landesanst., Neue Folge, Heft 16 (1895).

^{page 158 note 3} Six chambers are indicated in the figure.

^{page 159 note 1} Meek, F. B.: U.S. Geol. Explor. 40th Parallel, vol. iv (1877), pt. 1, p. 99.Google Scholar

^{page 159 note 1} Phillips, J.: “Figures and Descriptions of the Palæozoic Fossils of Cornwall, Devon, and West Somerset” (Mem. Geol. Surv.), 1841.Google Scholar

^{page 159 note 1} “Monograph of the Devonian Fauna of the South of England” (Pal. Soc.), pt. ii (1890).

^{page 159 note 1} Holzapfel (Abhandl. d. k. Preuss. geol. Landesanst., Neue Folge, Heft 16, 1895, p. 55 et seqq.) unites all these forms into one species—with several varieties—for which he retains Phillips's name inconstans, a species which he states to be confined to the Upper Middle Devonian.

^{page 159 note 1} Barrande, J.: Syst. Sil. de la Bohême, vol. ii, pt. 1 (1867), p. 29,Google Scholar pl. i, figs. 1–13; pl. ii, figs. 1, 2; pl. iii, figs. 15, 16; pl. ccxlii, fig. 1; pl. ccxliv, figs. 3, 4.

^{page 159 note 1} Ibid., p. 41, pl. iv, figs. 1–12.

^{page 160 note 1} See antea, p. 155, footnote.

^{page 160 note 2} Giebel, C. G.: Fauna der Vorwelt, Bd. iii (1852), p. 233.Google Scholar

^{page 160 note 3} Roemer, F. A.: Palæontographica, Bd. iii, Lief. 1 (1850), p. 16,Google Scholar spl. iii, fig. 18.

^{page 160 note 4} F. A. Roemer: ibid., p. 17, pl. iii, fig. 20.

^{page 160 note 5} Blumenbach, : Specimen Archæologiæ Telluris, 1803, p. 21,Google Scholarpl. ii, fig. 6.