NUGAHA GEOTTP 



257 



Fig. SLA profile or cardinal view of the preceding specimen, showing the strong elevated 

 laminos for muscular attachment. 



This feature of the interior is quite peculiar, and is alone su/Hcient to distinguish 

 the species. 



Position and locality. This species is more abundant in the vicinity of Rochester, than at 

 any other locality examined. It is also common at Marshall's mill in Sweden, and at Wolcott 

 in Wayne county, and less abimdant at Lockport and other western localities. In England, it 

 occurs in the Wenlock Limestone, and in the same position in the Island of Gothland. 



448. 23. LEPTiENA DEPRESSA. 



PL. LIII. Fig. 6a-l. 



Dritte Anomiten art mit breiter schlosskante. Hcpsch, Naturg. des Neiderdeutschland, 1781, 



Vol. 1, pag. 15, pi. 1, fig. 7 &8. 

 Anomites rhomboidalis. Wahlexberg, Acta Soc. S. Upsaliensis, 1821, Vol. viii, pag. 6.5, no. 7. 

 Producta depressa. Sowebby, Genera of Shells. 



— — In. Min. ConchologT, 1825, Vol. v, pag. 86, pi. 459, fig. 3. 



Producta rugosa. Hisinger, Vet. Acad. Handlingar, 1826, p. 33. 

 Productus depressus. Defranc, Diet, des Sciences nalurelles, 1826, Vol. xlvii, 353. 

 Lcptcsna rugosa. Dalman, Vet. Acad. Handlingar, 1827, pag. 106, pi. 1, fig. 1. 

 Leptesna depressa. Id. Ibid. pag. 107, pi. 1, fig. 2. 



Strophomena rugosa. Brojtn, Leth. geognostica, 1825, Vol. i, pag. 87, pi. 2, fig. 8. 

 Producta depressa. Phillips, Geol. Yorkshire, 1846, Vol. ii, pag. 215, pi. 8, fig. 18. 

 Productus depressus. Deshayes, 2d Edit. Lamarck An. sans vcrtebres, Vol. viii, p. 380. 

 Leptcena rugosa and L. depressa. Hisikger, Leth. suecica, 1837, pag. 69, pi. 20, fig. 2 & 3. 

 Orthis rugosa. Von Buch, Ueber Delthyris, 1837, p. 70. 

 Leptcena. Fischer, Oryct. du Gouv. du Moscou, 1837, p. 143. 



LeptcEna depressa. J. Sowerby in Murchison's Sil. System, 1839, pag. 623 & 636, pi. 12, fig. 2. 

 L. tenuistriata[?}. Id. Ibid. pag. 636, pi. 22, fig. 2 a. 



L. rugosa. Id. Trans. Geol. Soc. London, 1840, 2d series. Vol. v, pi. 56, fig. 4. 

 Orthis rugosa. Eichwald, Sil. Sy.st. in Eslhland, p. 162. 

 Leptcena rugosa. Phillips, Pal. Fossils, 1841, pag. 57, pi. 24. fig. 95. 

 I,, depressa. De KoNisfCK, Desc. An. Foss. de Belgique, 1842, pag. 215, pi. 12, fig. 3, 4, 5, 6 ; 



pi. 13, fig. 6. 

 L. — G. B. SowERBY, Conch. Manual, 1842, pag. 71, and pag. 300, fig. 206. 



Orthis rugosa. D'Archiac and De Vekneuil, Trans. Geol. Soc. London, 1842, 2d series, 



Vol. vi, part 2, p. 396. 

 Strophomena depressa. Vancxem, Geol. Rep. 3d Dist. New-York, 1842, pag. 79, fig. 5. 

 S. undulata. Id. Ibid. pag. 139, fig. 3. 



S. depressa. Hall, Geol. Rep. 4th Dist. New-York, 1843, pag. 77, fig. 5 ; pag. 104, fig. 2. 

 Orthis rugosa. C. F. Riemer, Rhein. Uebersgangsgebirge, 1844, pp. 85 & 90- 

 Lepl<zna depressa. De Verneuil, Geol. Russia and the Urals, 1845, Vol. ii, pag. 234, pi. 15, 



fig. 7. 



Shell semioval or semicircular ; hinge-line equal to, or extending beyond the width of the 

 shell ; dorsal valve having the upper part nearly flat, slightly convex or even concave, with 

 [ PAL.s;oNTOLOGy — Vol. ii.] 33 



