^{page 355 note 1} 1891, Band i. Zweites Heft. Breifl. Mittheil. ii. p. 210.Google Scholar

^{page 355 note 2} Leth. Rossica, 1860, vol. i. p. 1243.Google Scholar

^{page 355 note 3} Silurica, Fragmenta, Angelin and Lindström. 1880, p. 2.Google Scholar

^{page 355 note 4} The following is a translation of v. Schlotheim's description of “Orthoceratites vaginatus” (Petrefactenkunde, 1820, p. 53Google Scholar):— “Very beautiful and instructive examples from Reval, in Ueberg. Kalkst., some part still in the matrix, some free, and only about five inches long to a diameter of one inch; besides separate pieces of its remarkable siphuncle. Cf. Knorr, pt. iii. suppl. t. ivb. and Breynii opuscula, t. v. f. 2b., where this Orthoceratite, together with its elegant, somewhat cylindrical siphuncle is tolerably well portrayed. The length and thickness attained is, it appears, very considerable, whilst the siphuncle belonging to it is found of considerable stoutness. Its relation to the other part of the Orthoceratite is so important that it almost appears as a part of the shell-wall of the latter. It runs, moreover, close to one side of the shell, which in most of the representations of it is not properly indicated, and its protuberances have somewhat of a screw shape; very ornamental, as if elaborately designed. The shell itself is very distinctly oblique, with sharp, somewhat forwardly projecting lines, striated in the direction of the chambers, which latter are bent inwards somewhat stronger towards the siphuncle.”

^{page 355 note 5} An island in the Baltic, off the east coast of Sweden.

^{page 356 note 1} Lethæa Suecica, 1837, p. 28,Google Scholar Tab. ix. fig. 7. The name Orthoceras [Endoceras] trochleare appears to have been originally bestowed by Dalman. See Hisinger's, Auteckningar i Physik och Geognosie, femte häftet, 1831, p. 12,Google Scholar Tab. iv. fig. 3.

^{page 357 note 1} Schrift. der physikal-ökonom. Gesell. zu Königsberg, Jahrg. xxii. Abth. i. p. 93,Google Scholar Taf. iv. ff. 5, a–d.