428 THE LIAS AMMONITES. 



the Upper Lias at Whitby and Boulby, in Yorkshire; Lyme Regis, Dorsetshire;. 

 Dumbleton and Alderton, Gloucestershire. The Whitby specimens are by far the most 

 beautiful and best preserved. 



Forei(/n Distribution. — In France it has been collected at Pontaine-Etoupe-Four, 

 Croiselle, Calvados; Charolles, Saone-et-Loire ; Thouars, Deux-Sevres ; Cheville, Sarthe ; 

 Avallon, Yonne; Semur, Cote-d'Or ; Mende, Lozere ; Verpilliere, Isere; Saint-Rambert,. 

 Ain ; Gundershoffen, Haut-Rhin. 



Luxevtbourf/ . — In the Marnes de Grande Cour. 



In Germany. — In the Posidonomyen-schiefer of Altdorf, Bavaria, Boll, and. 

 WiJrttemberg. 



Phylloceras subcarinatdm, Youvf/ and Bird. PI. LXXXI, figs. 1, 2, 3. 



Nautilus subcauinatus. Young and Bird. Geol. York. Coast, p. 255, pi. xii, 



fig. 7, 1822. 



Ammonites — Phillips. Geol. of Yorkshire, p. 167, pi. xiii, fig. 3, 1835. 



— — Simpson. Monogr. on Ammonites, p. 8, 1843. 



— — Morris. Catalogue of British Fossils, p. 145, 1843. 



— — Cq^mZ/o. Ammonit.Jelle Alps. Venete, pi. 13, fig. 3, 1846. 



— — Bronn. Index Palseontologicus, p. 60, 1848. 



— — Giebel. Fauna Vorwelt, Bd. iii, p. 747, 1852. 



— — Morris. Catalogue of British Fossils, 2nd ed., p. 295,. 



1854. 



— — Oppel. Die Juraformation, p. 251, 1855. 



— — Simpson. Fossils of York. Lias, p. 37, 1855. 



— — Guembel. Beschr. d. Bayr. Alpen, p. 474, 1861. 



— — Oppel. Palaontoi. Mittheilungen, p. 140, pi. 44, figs. 



1, 2, 1862. 

 Phylloceras subcarinatum, Tate and Blake. Yorkshire Lias, p. 297, 1S76. 



Diagnosis. — Shell discoidal, extremely involute, inner volutions nearly concealed,, 

 outer vv'horl one-half the diameter of disk ; sides convex, inflated, covered with straight or 

 slightly tlexed obtuse irregular radii, obsolete near aperture ; strise very numerous, fine, 

 annular, irregular, diverging ; siphonal area wide, with central ridge, and two flattened 

 bands on each side ; umbilicus narrow and deep. Aperture ovate, widest at the spiral 

 border and bevelled away towards the area. 



Dimensions. — Transverse diameter ] 00 milhmetres; breadth of area IS millimetres; 

 height of aperture 50 millimetres; width of whorl at the aperture 40 millimetres; width 

 of umbilicus 1 5 millimetres. 



Description. — Phylloceras subcarinatum has been long known to the Yorkshire 

 naturalists, and is remarkable for its dissimilarity from other congeneric forms ; still this 



