PALAEONTOLOGY OF NEW YORK. 
Genus LEPTON A, Dalman. 1828. 
PLATE VIII, FIGS. 12-31; AND PLATE XV A, FIGS. 40-43. 
1769. Conchites, Wilckens. Nachricht von seltenen Verstein., p. 77, pi. viii, figs. 43, 44. 
1821. Anomites, Wahlenberg. Nova Acta Soc. Sci. Upsalae, vol. viii, p. 65. 
1823. Produda, Sowerby. Mineral Conchology, p. 86, pi. cccclix, fig. 3. 
1826. Produda, Hisinger. Acta Acad. Sci. Holm, p. 338. 
1828. Leptcena, Dalman. Uppstallning och Beskrifning af de i Sverige funne Terebratuliter; Kongl. 
Yetenskaps-Academiens Handlingar, for ar 1827, pp. 94-96, 106, 107, 
pi. i, figs. 1, 2. 
1834. Leptcena, Kloden. Die Verstein. der Mark Brandenburg, p. ISO. 
1837. Orthis, von Buch. Ueber Delthyris oder Spirifer und Orthis, p. 30. 
1837. Leptcena, Hisinger. Lethaea Suecica, p. 69, pi. xx, figs. 2, 3. 
1837. Leptcena, m Fischer de Waldheim. Oryctogr. du Gouv. de Moscou, p. 143. 
1839. Leptcena, J. de C. Sowerby. In Murchison’s Silurian System, pp. 623, 636, pi. xii, fig. 2. 
1840. Orthis, von Eichwald. Silurische Schichten-System von Esthland, p. 162. 
1841. Leptcena, Phillips. Palaeoz. Foss. Cornwall, Devon and West Somerset, p. 51, pi xxiv, fig. 95. 
1841. Strophomena, Conrad. Fifth Ann. Rept. N. Y.Geological Survey, p. 54. 
1842. Leptcena, de Koninck. Descr. Anim. Foss, dans le Ten*. Carbonif. Belgique. 
1842. Strophomena, Vanuxem. Geology of N. Y. ; Rept. Third Dist., pp. 79, 139, fig. 53. 
1843. Strophomena, Hall. Geology of N. Y. ; Rept. Fourth District, pp. 77, 104, fig. 52 ; p. 175, fig. 3. 
1843. Produdus?, de Castelnau. Essai sur le Systeme Silurien de l’Amerique Septentrionale, p. 39, 
pi. xiii, fig. 7. 
1844. Orthis, F. Rcemer. Das Rhein. Uebergangsgebirge, pp. 85, 90. 
1844. Leptagonia, McCoy. Synopsis Carb. Foss. Ireland, p. 116. 
1845. Leptcena, de Verneuil. Geol. Russie de l’Europe et des Mont, de l’Oural, p. 234, pi. xv, fig. 7. 
1846. Leptcena, King. Annals and Magazine Natural History, vol. xvii, pp. 28, 36. 
1847. Leptcena, Davidson. London Geological Journal, p. 54, pi. xii, figs. 12-16. 
1847. Leptcena, Hall. Palaeontology of N. Y., vol. i, p. 108, pi. xxxi a, fig. 4. 
1848. Leptcena, Davidson. Bull. Soc. Geol. de France, Ser. 2,- vol. v, p. 306, pi. iii, fig. 3. 
1848. Produdus, Davidson. Bull. Soc. Geol. de France, Ser. 2, vol. v, p. 315, pi. iii, fig. 1. 
1850. Leptcena, King. Monograph Permian Fossils of England, pp, 81, 104. 
1852. Leptcena, Hall. Palaeontology of N. Y., vol. ii, pp. 62, 257, pi. xxi, fig. 8; pi. liii, fig. 6. 
1856. Strophomena, Billings. Canadian Nat. and Geol., vol. i, p. 59, pi. i, fig. 5. 
1857. Strophomena, Hall. Tenth Rept. N. Y. State Cab. Nat. Hist., p. 55. 
1859. Leptcena, von Eichwald. Lethaea Rossica, vol. i, p. 867. 
1859. Leptcena, Hall. Twelfth Rept. N. Y. State Cab. Nat. Hist., p. 82. 
1859. Strophomena, Hall. Palaeontology of N. Y., vol. iii, p. 195, pi. xix, fig. 1; p. 417, pi. xciv, figs. 2, 3. 
1860. Strophomena, F. Rohmer. Silurische Fauna westlichen Tennessee, p. 66, pi. v, fig. 2. 
1861. Strophmnena, Billings. Canadian Journal, vol. vi, p. 336, figs. Ill, 112. 
1863. Strophomena, Billings. Geology of Canada, p. 311, fig. 314; p. 367, fig. 373. 
1863. Strophomena, Billings. Proc. Portland Soc. Nat. Hist., p. 107, pi. iii, fig. 1. 
1865. Leptcena, Shaler. Bull. No. 4, Mus. Comp. Zool., p. 65. 
1867. Strophomena, Hall. Palaeontology N.Y., vol. iv, p. 76, pi. xii, fig. 16-18; p. 414, pi. xv, figs.15,16. 
1868. Strophomena, Meek and Worthen. Geology of Illinois, vol. iii, p. 426, pi. x, fig. 7. 
1873. Strophomena, Meek. Palaeontology of Ohio, vol. i, p. 75, pi. v, fig. 6. 
1874. Strophomena, Billings. Palaeozoic Fossils, vol. ii, p. 27. 
1874. Strophomena, James. Cincinnati Quart. Jour. Sci., vol. i, p. 333. 
1875. Strophomena, Miller. Cincinnati Quart. Jour. Sci., vol. ii, p. 55. 
