178 
NAUTILOIDEA. 
ActinoceraS) sp. 
[Cf. Actinoceras coclileatum^ infra.] 
Two imperfect specimens of an Actinoceras from Norway are com- 
parable in many respects with the above species. One of them shows 
what appears to be the outer surface of the test, and it is perfectly 
smooth. Both these specimens are weathered longitudinal sections 
exposed upon the surface of the rock, but the matrix having been 
removed from beneath them, the shell is thus laid bare on that side. 
The septa are somewhat closer than they are in most examples of 
A. cochleatum ; but in other features, such as the dimensions of the 
siphuncle, the rate of tapering, &c., the forms under discussion agree 
fairly well with that species. 
Horizon. Etages 7 and 6 (=Valentian ?). 
Locality. Lango Island, near Holmstrand, Norway. 
Actinoceras cochleatum, Schlotheim, sp. 
1731. Tuhuli coyicamerati-cylindriformes^ Klein, Descrip, tiibuloruin 
marinorum, Appendix, p. 8, tab. ii. ff. 3, 4. 
1732. Species ix. Orthoceratites siphone ad peripheriam &c., Breyniii'<, 
Dissertatio physica de Polythalamiis, p. 37, tab. vi. ff. 1, 2. 
1813. Orthoceratites cochleatus, Schlotheim, Leonhard’s Taschenb. fiir 
Mineralogie, Abth. i. p. 34. 
1820. Orthoceratites cochleatus, Schlotheim, Die Petrefactenkimde, 
p. 55. 
1821. Orthoceratites crassiventris, Wahlenberg, Nova Acta Reg. Soc. 
Scient. Upsaliensis, vol. viii. p. 90. 
1831. Orthoceratites crassiventris, Hisinger, Anteckn. i Physik och 
Geognosie, Haft. v. p. 112, tab. iv. f. 9. 
1837. Orthoceratites crassiventris, Hisinger, Lethaea Svecica, p. 30, 
tab. X. f. 3. 
1840. Orthoceratites cochleatus, Qiienstedt, Neiies Jahrb. p. 264. 
1842. Orthoceratites cochleatus, Eichwald, Die ‘Urwelt Russlands, 
Heft ii. p. 24. 
1845. Orthoceratites cochleatus, Murch., de Yern., and de Keyserl. Geol. 
de la Russie d’Europe, pt. 3, p. 393. 
1846. Orthoceratites cochleatus, Quenstedt, Petrefactenkunde Deutsch- 
lands, Band i. Abth. i. p. 42, tab. i. f. 6 {not f. 8). 
1849. Orthoceratites cochleatus, Quenstedt, Die Cephalopoden, p. 42, 
tab. i. f. 6. 
1852. Orthoceras cochleatum, Giebel, Fauna der Yorwelt, Band iii. 
Abth. i. p. 242. 
1855. Orthoceras crassiventre, Barrande, in Leonhard and Broun's 
Neues Jahrb. p. 402. 
