RHYNCHONELLA. 71 



the peculiar disposition of the plaits in the duplicates, forming a natural passage by means of 

 the plicoscB into the dichotemce ; these authors are, however, mistaken, in stating that 

 the small group in question belongs exclusively to the Lias period, as several similar 

 species are found in the Cretaceous beds, such as B. antidicholoma (Bouvignier), &c, and 

 T. Schnurii (de Ver) from the Devonian Rocks. 



Both B. rimosa and furcillata are generally found in the same localities in the Middle 

 Lias, 1 but in England they are rather uncommon fossils ; I have found B. rimosa in the 

 Lias at Farrington Gurney, near Radstock, also near Cheltenham, and it has likewise been 

 met with near Whitby. In France, it is common at Vieux Pont, Fontaine-Etoupefour, 

 &c, near Caen, at St. Amand (Cher), at Bajac, Castellane (Lower Alps) ; and it is stated 

 by Von Buch and Mr. Fraas to occur plentifully in many German localities, such 

 as Bahlingen in Wurtemberg, in the stream of Pliensbach, Amberg, Allem, &c. : fig. 6, 

 nat. size; fig. 6 a , enlarged. 



65. Rhynchonella spinosa, Schloth., Sp. Plate XV, figs. 15 — 20. 



Terebratclites spinosus, Schlotheim, 1813. Beitriige zur Naturgeschichte der 



Versteinerungen in Leonhards, Mineral Taschenbach, 

 vol. vii. Refer to Knorr's fig. in Lapides Diluvii 

 Universalis Testes, 1/55, tab. b iv, fig. 4. 



Terebratdla spinosa, Smith, 1816. Stratigrapliical System of Organised Fossils, p. 108. 

 — senticosus, Schl. 1820. Der Petrefac, p. 268, No. 30. 



Terebratula aspera, Kceniff, 1825. Icon. Sect., No. 219. 



— spinosa, Lamarck, 1819. An. sans Vert., vol. vi, No. 52 ; and Dav., Notes 



on tbe Species of Lamarck, An. and Mag. of Nat. Hist., 1850. 



— — Von Buch, 1834. Uber Ter. ; and 1838, Mem. de la Soc. 



Gcol. de France, l re ser., p. 161, pi. xvi, fig. 4. 



— — Defrance, 1828. Vol. liii, Die. d'Hist. Nat., p. 161. 



— — Zieten, 1832. Die Vers., Wiirt., p. xliv, fig. I. 



— — Deslongchamps, 1837. Soc. Linn, de Normandie, p. 30. 



— — Phillips, 1835. Geol. of York, vol. i, pi. ix, fig. 18. 



— — Bronn. Leth. Geog., 1837, p. 296, tab. xviii, fig. 2. 



— — Quenstedt, 1843. Flozgebirge. 



— — Morris, 1843. Catalogue. 



— — Tennant, 1847. A Stratigrapliical List of Br. Foss., p. 74. 



— — Bronn. Index Pal., 1848, p. 1251. 

 Hemithiris spinosa, D'Orb. 1849. Prodrome, vol. i, p. 286. 



Acanthothis spinosa, B'Orb. Pal. Franc. Ter. Cretacees, vol. iv, p. 343, 1847, (but 

 publisbed later.) 



1 In a very interesting paper ' On the Comparison of the German Jura Formations with those of France 

 and England' by M. Oscar Fraas, (Leonhard's and Bronn's Neues Jabrbucb, f. Min., U.S.W., 1850, 2 H, 

 pp. 138 — 185,) this species is particularly noticed as a most characteristic form in the Middle Black Jura 

 in all countries, and is stated to be always found with T. numismalis. I cannot, however, believe with that 

 author, that T. digona and T. lagenalis were found so low down as the Middle Lias. 



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