Hostname: page-component-5c6d5d7d68-ckgrl Total loading time: 0 Render date: 2024-08-19T12:37:59.957Z Has data issue: false hasContentIssue false
  • English
  • Français

IV.—Notes on Ammonites

Published online by Cambridge University Press:  01 May 2009

L.F. Spath
Get access Rights & Permissions [Opens in a new window]

Extract

A character of the suture-line that has received considerable attention lately is the obliquity with regard to the radius. Of course, it had long been noticed that suture-lines may vary in the form and foliation of their elements (brachyphyllic, dolichophyllic, and leptophyllic suture-lines of Mojsisovics, and euryphyllian and stenophyllian suture-lines of Haug) as in their general course. There maybe (externally) a strong convexity forward (Cyclololus), a straight (Sphenodiscus) or wavy line (Pseudosageceras), or a convexity backward (Protengonoceras). Again, the suture-line may be inclined strongly forward towards the umbilicus (Cheltonia) or have a retracted or dependent inner portion (Psiloceras). It is this Litter obliquity that has been used as a generic and even family distinction, e.g. by Mr. Buckman, to determine the affinity of Bredya with Hammatoceratidse, and not Hildoceratidæ.

Type
Original Articles
Information
Geological Magazine , Volume 6 , Issue 2 , February 1919 , pp. 65 - 71
Copyright
Copyright © Cambridge University Press 1919

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 65 note 1 “Die Cephal. d. Hallstätter Kalke”: Abh. k.k. Reichsanst., vol. vi, p. 2, 1873–1893Google Scholar.

page 65 note 2 “Les Amm. du Permien et du Trias”: Bull. Soc. Géol. France, ser. III, vol. xxii, p. 409, 1894.Google Scholar

page 65 note 3 “Certain Jurassic (Lias-Oolite) Strata of South Dorset; and their Correlation”: Q.J.G.S., vol. lxvi, pp. 97–8, 1910.Google Scholar

page 65 note 4 “Development of Tragophylloceras Loscombi”: Q.J.G.S., p. 352, 1914Google Scholar.

page 65 note 5 Pal. Soc., vol. i, 1887–1907.Google Scholar

page 65 note 6 “Beitr. Kenntn. Tief. Zonen Unt. Lias Nordöstl. Alpen”: Beitr. Geol. Pal. Österr.-Ung., vol. iv, pts. iii, iv, pp. 190–202Google Scholar.

page 65 note 7 “Die Degenerierten Perisphinctiden des Kimmeridge von Le Havre”: Abh. Schweiz. Pal. Ges., vol. xxiii, p. 41.Google Scholar

page 65 note 8 “Etude sur les Cardioceratidés de Dives, etc.”: Mem. No. 45 Soc. Géol. France, Pal. i, 19, fasc. ii, p. 14Google Scholar.

page 66 note 1 The presence of a high internal saddle in certain Japanese Scaphites induced Yabe (“Die Scaphiten a. d. Oberkreide von Hokkaido”: Beitr. Pal. Österr.-Ung., etc., vol. xxiii, p. 167, 1910Google Scholar) to create a new genus, Yezoites; but the writer would agree with Nowak, (in “Untersuchungen ü. Cephal. Ob. Kreide in Polen”, ii, Die Skaphiten: Extr. Bull. Acad. Sci. Cracovie, 07, 1911, p. 549)Google Scholar, who cannot admit that the internal portion of the suture-line of Ammonites is the most important as regards the determination of their relations, though “it must not be underestimated or, still less, neglected, as is still done very often at the present day”.

page 66 note 2 Horn, , “Die Harpoceraten der Murchisonæ-Schichten des Donau-Rhein-Zuges”: Mitt. Grossh. Bad. Geol. Land. Anst., vol. vi, pt. i, p. 264Google Scholar.

page 66 note 3 Neumayr, , “Kenntn. Fauna Unterst. Lias i. Nordalpen”: Abh. k.k. Reichsanst., vol. vii, pt. v, p. 25, pl. iv, figs. 6a, b, 1879Google Scholar.

page 67 note 1 Palœontographica, vol. li, pts. v, vi, p. 259, 1905Google Scholar.

page 67 note 2 “Notes sur les Oxynoticeras du Sinémur. Supér. du Portugal, etc.”: Comm. Serv. Geol. Portug., vol. vi, pt. ii, p. 219, 1905Google Scholar.

page 67 note 3 Op. cit., 1914, p. 346.

page 67 note 4 Op. cit., i, p. 510, 1906.

page 67 note 5 “The Growth of the Cephalopod Shells”: Geol. Mag., Dec. III, Vol. IV, pp. 446–9, 10, 1887Google Scholar; and “Shell-growth in Cephalopoda (Siphonopoda)”: Ann. Mag. Nat. Hist., ser. vi, vol. i, pp. 298–310, 04, 1888Google Scholar.

page 67 note 6 “The Evolution and Classification of the Cephalopoda, an Account of Recent Advances”: Proc. Geol. Assoc., vol. xii, p. 291, 1892Google Scholar.

page 67 note 7 Proc. Geol. Soc., No. 979, p. 3, 11 11, 1915Google Scholar.

page 68 note 1 Op. cit., vol. ii, p. 214.

page 68 note 2 “The Fossils and Stratigraphy of the Middle Devonic of Wisconsin”: Wisc. Geol. and Nat. Hist. Surv., Bulletin No. xxi, 6, 1911Google Scholar.

page 68 note 3 Système Silurien de la Bohème, vol. iii (Cephal.), 1867–1877Google Scholar.

page 68 note 4 “Observations on the genus Polymorphites”: Geol. Mag., n.s., Dec. VI, Vol. IV, pp. 443–4, figs. 1, 11, 10, 1917Google Scholar. The writer cannot accept the derivation of this genus from the much earlier arietid Agassiceras development, Cymbites, and will refer later to the resemblance in the sutural development.

page 69 note 1 Op. cit. (Cardioceratidés), p. 61, fig. 60.

page 69 note 2 “Can the Sexes in Ammonites be distinguished?”: Nat. Sci., vol. iv, p. 430, 06, 1894Google Scholar.

page 69 note 3 The Eocene Mollusca, pt. i: Cephalopoda (Pal. Soc. Mon.), 1849, p. 44Google Scholar.

page 70 note 1 Loc. cit. (in Zittel-Eastman, 1900), p. 544.

page 70 note 2 “Anatomy of Nautilus pompilius”: Proc. Zool. Soc., 1895, pp. 664–86Google Scholar (quoted in Zittel-Eastman, 1900, p. 506).