This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1908 Excerpt: ... is characteristic of Paralegoceras. Dr. K. von Zittel confines Gastrioceras to forms with a single pair of lateral lobes. But the relations of Gastrioceras, Glyphioceras, Goniatites, and Paralegoceras have been best worked out by Karpinskv, who shows that there is no marked distinction between Goniatites and ...
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This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1908 Excerpt: ... is characteristic of Paralegoceras. Dr. K. von Zittel confines Gastrioceras to forms with a single pair of lateral lobes. But the relations of Gastrioceras, Glyphioceras, Goniatites, and Paralegoceras have been best worked out by Karpinskv, who shows that there is no marked distinction between Goniatites and Gastrioceras; that both have the same number of lobes and saddles--nine of each; that the second pair of lateral lobes may be on the umbilical shoulders or on the sides of the shell, thus differing from Paralegoceras, in which the third pair of lateral lobes is on the umbilical shoulders. Gastrioceras usually has a trapezoidal cross section and umbilical ribs; but some species lack the a Proc. Boston Soc. Nat. Hist., Vol. XXII, p. 327. 6 Ibid. c Second Ann. Rept. Geol. Surv. Texas, p. 355. 'Ibid. Grundziige der Palreont., p. 399. ribs, as G. globulosum Meek and Wortheu, while some species of Glyphioceras have umbilical ribs and, in their youth, also the elliptical cross section, as Glyphioceras diadema Goldfuss. But the two extremes are widely separated from each other, as Gastrioceras jossce Veraeuil and Goniatites sphcericus Martin. This genus has been looked upon by Steinmann as the ancestor of the trachyostracan families of the Trias, the Ceratitidae and the Tropitidae. Dr. K. von Zittel agrees with this opinion as to the origin of the Tropitidae, but thinks the Ceratitidae developed out of the Prolecanitidae, which is in agreement with the writer's studies on the development of Ceratites of the Trias. Gastrioceras Rranneri Smith. PL XI, figs. 8-13. 1896. Gastrioceras branneri, J. P. Smith, Proc. Am. Philos. Soc., "Vol. XXXV, p. 257, PI. XXIII, figs. 1-6. The adult shell is discoidal, with low, narrow whorls of semilunular cross section; the a...
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Add this copy of The Carboniferous Ammonoids of America to cart. $19.72, new condition, Sold by Ingram Customer Returns Center rated 5.0 out of 5 stars, ships from NV, USA, published 2022 by Legare Street Press.
Add this copy of The Carboniferous Ammonoids of America to cart. $29.16, new condition, Sold by Ingram Customer Returns Center rated 5.0 out of 5 stars, ships from NV, USA, published 2022 by Legare Street Press.