"Vol. 69.] " CERTAIN UPPER JURASSIC STRATA OF ENGLAND. 423 



19. Certain Upper Jurassic Strata of England. By Dr. Hans 

 Saleeld, University of Gottingen. (Communicated by S. S. 

 Buckman, F.G.S. Head June 11th, 1913.) 



[Plates XLI & XLIL] 



By combining the evidence of a number of sections in England 

 and near Boulogne-sur-Mer I have succeeded in establishing a 

 normal succession of zones in the Oxfordian. Kimmeridgian, and 

 Portlandian rocks, using these terms according to the German 

 and Erench classifications. Dispensing with A. d'Orbigny's 

 separate stage of the Corallian, I agree with Oppel in extending 

 the ' Oxfordian ' stage up to the ' Kimmeridge,' the lowest zone of 

 which, in accordance with the view of H. Douville, A. de Lapparent, 

 . and E. Haug, I recognize to be that characterized by Pictonia baylei, 

 sp. nov. (=Pictonia eymodoce Bayle, 1 Tornquist, and others, non 

 Ammonites eymodoce d'Orbigny). Further, 1 divide the Oxfordian 

 into two portions: the lower chiefly yields Cardioceraia of the 

 ; groups of cor datum and tenuicostatum, ending above with the 

 . zone of Perisphinctes martelli Oppel sp. and P. biplex de Loriol 2 

 (Ammonites martelli auctt., non A. biplex Sow.) ; the upper 

 comprises the following zones in ascending order : — (1) Zone 

 with Perisphinctes wartce Bukowski, Cardioceras (Amoeboceras) 

 alternans von Buch sp. and allied species ; (2) Zone with Peri- 

 sphinctes decipiens J. Sow. sp., P. acliilles d'Orb. sp., and Cardio- 

 ceras (Amuaboceras) serratum J. Sow. sp.; (3) Zone with Ringsteadia 

 [ gen. nov. Ypseudocordatus Blake sp.( = Ammonites mutabilis Damon, 

 Proplanulites mutabilis II. Douville, non A. mutabilis J. de C. Sow.) 

 and other species of this new genus. 



The Kimmeridgian in the German and Erench sense would com- 

 prise the following zones, taken in ascending order : — (1) Zone with 

 Pictonia baylei sp. nov. and other species of Pictonia ; (2) Zone 

 with Rasenia [gen. nov.] 4 eymodoce d'Orb. sp., R. uralensis d'Orb. 

 sp., R. thermarum Oppel sp., in addition to others, and, further, 

 Curdiocerata which have invariably been described as Cardioceras 

 alternans von Buch sp., but belong to other species and other 

 groups; for example, C. hitchini sp. nov. ( = Ammonites alternans 

 H. B. Woodward, ' Jur. Bocks of Britain' Mem. Geol. Surv. vol. v, 

 1 895, fig. 68, p. 155) ; (3) Zone with Rasenia mutabilis J. de C. Sow. sp. 



1 E. Bayle, 'Explication de la /Carte geologique de la France' vol. iv (J878) 

 pi. Ixvi ; A. Tornquist, ' Die degenerierten Perisphinctiden des Kimmeridge 

 von Le Havre' Abhandl. Schweiz. Palaont. Gesellsch. vol. xxiii (1896) pi. ii, 

 pi. iii, figs. 1-2, & pi. iv, fig. 1. The genus Pictonia has hitherto been found 

 exclusively in Northern France, England, and North Germany (Pomerania). 



2 P. de Loriol, 'Oxf'ordien superieur & moyen du Jura Ledonien ' Abhandl. 

 Schweiz. Palaont. Gesellsch. vol. xxx (1903) pi. vi. 



3 See p. 427. * See p. 429. 



•Q.. J. G. S. No. 275. 2 e 



