286 PALEONTOLOGY OF NEW YORK. 



Gemus PENTAMERUS, Sowerby. 1813. 



PLATKS LXVII, LXVUI, LXIX, LXX. 



1813. Pentatnerus, J. Sowbrbt. Mineml Concholo^, vol. i, p. 76, pi. xxviii. 



1839. Pentainenui, i. db C. Sowkrby. Silurian System, pi. xix, figs. 9, 10. 



1843. Pentamerui, Hail. Geology of New York ; Rept. Fourth Dist., p. 70, figs. 1-5. 



1845. Pt^itcimeriis. db Vbrnki-il. Geologie de la Russie, p. 119, pi. viii, figs. la-c. 



1852. Pentaiiuruii, Hall. PaliRontology of New York, vol. ii, p. 79, pi. xxv, figs, lo-ni; pi. xxvi, 



figs. 1 a-d; p. 103, pi. xxxi, fig. 1. 



1854. Pentatnerus, Eichwald. Bull. Soc. Imp. Natural. Moscou, pi. 1, p. 91. 



1854. Pentamerus, F. Schmidt. Neueste Untevsuch. ueber Brachiopoilen, p. 213. 



1859. Pentamerus, Eichwald. Lethsea rossica, vol. i, p. 788, pi. xxxiv, fig. 23. 



1861. Pentamerus, McCubskby. New Palieozoio Fossils, p. 85. 



1S63. Pentatnerus, Billings. Geology of Canada, p. 316, fig. 326. 



1866. Pentamerus, Billings. Catalogue Silur. Fossils Anticosti, p. 45. 



1867. Pentamerus, Davidson. British Silurian Brachiopoda, p. 151, pi. xviii, figs. 1-12; pi xix, figs. 1, 2. 



1867. Pentatnerus, Hall. Palsontology of New York, vol. iv, pp. 369-374. 



1868. Pentamerus, McCHuaNKY. Trans. Chicago Acad. Sci., vol. i, pi. ix, fig. 1. 



1872. Pentatnerus, Hall and Whitfibld. Twenty-fourth Ann. Rept. N. Y. State Mus. Nat. Hist., 



p. 183. 

 1875. Pentatnerus, Hall and Whitfibld. Twenty-seventh Ann. Rept. N. Y. State Mus. Nat. Hist., 



pi. X, figs. 13, 14. 

 1875. Pentatnerus, Hall and Whitfibld. Palajontology of Ohio, vol. ii, pp. 137, 139, pi. vii, tigs. 9-11. 

 1882. Pentatnerus, Whitfibld. Annals N. Y. Acad. Science, vol. ii, p. 195. 

 1882. Pentatnerus, Whitfibld. Geology of Wisconsin, vol. iv, pp. 288, 291, pi. xvii, figs. 3-9. 

 1889. Pentatnerm, Nbttklroth. Kentucky Fossil Shells, pp. 60-62, pi. xxix, figs. 23, 24 ; pi. xxx, 



figs. 2-i. 



1889. Pentamerus, Fobrste. Proc. Boston Society Nat. Hist., vol. xxiv, p. 324, pi. v, figs. 17, 18. 



1890. Pentamerus, Whitfibld. Annals N. Y. Acad. Sci., vol. v, p. 513, pi. v, tigs. 11-22. 



1890. Pentatnerus, Gagel. Die Brachiop. der camb. iind silur. Geschiebe im Diluvium der Provinzen 

 Ost- und Westpreussen, p. 53, pi. iv, fig. 1. 



Since it seems necessary to restrict the term Conchidium to those pentame- 

 roids embraced by de Verneuil in his division " plisses, sans sinus," it becomes 

 desirable to apply the designation Pentamerus to the second division of those 

 shells, the " lisses, sans sinus." This use of Sowerby's term is in precise 

 accordance with recognized rules of nomenclature. The first species cited by 

 Sowerby, and that which has been generally regarded as typical of the genus 

 by authors who have preferred this term to the earlier designation of Linne, 

 is P. Knighii, a plicated shell, which belongs to Conchidium.* The second of 

 Sowbbby's typical examples, and that to which must be accorded his generic 



* The P. Aylesfordl, Sowerby, cited in the " Mineral Conchology " as another of the typical species of 

 Pbhtambrdb, was su>>8equently regarded by that author as a synonym for P. Knighti (Silurian System, 

 p. 615, 1839), and the name has consequently fallen Into disuse. 



