Hostname: page-component-7479d7b7d-t6hkb Total loading time: 0 Render date: 2024-07-11T07:07:01.410Z Has data issue: false hasContentIssue false
  • English
  • Français

The Ontogeny of Certain Arietidan Oxycones

Published online by Cambridge University Press:  01 May 2009

T. Neville George
T. Neville George
Affiliation:
University College of Swansea.
Get access Rights & Permissions [Opens in a new window]

Extract

The compressed angustumbilicate oxycones of the Deiran and Raasayan stages of the Lower Lias are generally assumed to be “homoeomorphous terminals of different lineages” of the Arietidae. But while the characters of the adult sutures of these forms link them with that family, there is comparatively little evidence as to the details of the ontogenetic developments of the various genera hitherto recognized. It is the purpose of this paper to repair this deficiency in some slight measure. The two forms selected, partially for convenience, are of considerably different ages: Victoriceras is a Raasayan form, while Oxynoticeras oxynotum occurs at a considerably lower horizon in the Deiran.

Type
Original Articles
Information
Geological Magazine , Volume 67 , Issue 8 , August 1930 , pp. 352 - 361
Copyright
Copyright © Cambridge University Press 1930

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

page 352 note 1 Buckman, S. S., “Jurassic Chronology—1: Lias,” Q.J.G.S., vol. lxxiii, 1917, p. 288.Google Scholar

page 352 note 2 Tutcher, J. W. and Trueman, A. E., “The Liassic Rocks of the Radstock District,” Q.J.G.S., vol. lxxxi, 1925, p. 613.Google Scholar

page 354 note 1 Specimen figured in Buckman, S. S., Type Ammonites, vol. iii, 1919, pl. cxxxvi.Google Scholar

page 356 note 1 Richardson, L., “The Lias at the Gas Works, Gloucester,” Trans. Woolhope Nat. Field Club (1914–1917), 1918, p. 154.Google Scholar

page 356 note 2 Trueman, A. E. and Williams, D. M., “Notes on Some Lias Ammonites from the Cheltenham District,” Proc. Cotteswold Nat. Field Club, vol. xxii, pt. 3, 1926, p. 251.Google Scholar

page 356 note 3 S. S. Buckman, op. cit., 1919, pl. cxliii.

page 356 note 4 Buckman, S. S., “Jurassic Chronology: I—Lias, Supplement I, West England Strata,” Q.J.G.S., vol. lxxvi, 1920, p. 62;CrossRefGoogle Scholar Buckman, S. S., op. cit., 1917, p. 269.Google Scholar

page 357 note 1 Specimen figured in S. S. Buckman, op. cit., 1919, pl. cxliii.

page 360 note 1 Trueman, A. E. and Williams, D. M., “Studies in Ammonites of the Family Echioceratidae,” Trans. Roy. Soc. Edin., vol. liii, pt. iii, 1925, p. 701.Google Scholar