12 PALAEONTOLOGY OF NEW YORK. 



Costes, subdivided into the costes (= Spirifer ?, Pentamerus ?) and costato-stries, 

 the latter including a radiate species and Enteletes Lamarcki ; IV. Plisses, sub- 

 divided into the aperturati, with sinus plicate, and ostiolati, with sinus smooth; 

 terms which had already been proposed by von Buch, and were derived from 

 Schlotheim's species, S. aperturatus and S. ostiolatus. 



QuENSTEDT, in 1871, adopted these last-named divisions and added the 

 division Rostrati, for species in which the hinge-line is short; this chaotic 

 assemblage was made to include the smooth species of the Palaeozoic (Martinia 

 and Reticularia) as well as the Spiriferinas of the Carboniferous and 

 Mesozoic. 



In the American Palaeozoic there are probably not less than two hundred 

 species of the genus Spirifer. Representatives of the greater number of these 

 have passed under our examination, and they, with the aid of not a few species 

 unknown in American faunas, have furnished the evidence upon which the 

 following proposed arrangement is based : 



I. Radiati. Typical example, Spirifer radiatus, Sowerby (including S. plicat- 

 ellus, Sowerby). 



(I)* 1840. Delthyris, Conrad. Geol. Suvv. N. Y., Pal. Dept. ; Fourth Ann. Kept., p. 207. 



(1) 1842. Delthyris, Conrad. Journ. Acad. Nat. Sci. Phila., vol. viii, p. 261, pi. xiv, fig. 17. 



(2) 1842. Delthyris, Conrad. Journal Acad. Nat. Sci. Philadelphia, vol. viii, p. 261. 

 (1) 1842. DeWiyr'is, Vandxem. Geology of N. Y. ; Kept. Third Dist, p. 120, tig. 1. 



(1) 1843. Spirifer, Ca.stelnad. Essai sur le Systfeme Silur. de I'Amer. Septen., p. 41, pi. xiii, fig. 5; 



p. 42, pi. xiii, fig. 4. 

 (1) 1843. Delthyris, Mather. Geology of N. Y. ; Kept. First Dist., p. 343, fig. 1. 



(1) 1843. Delthyris, Hall. Geology of N. Y. ; Kept. Fourth Dist.. p. 105, fig. 2 a, b. 



(2) 1843. Delthyris, Hali.. Geology of N. Y. ; Rept. Fourth Dist., p. 105, fig. 1 ; p. 269, fig. 1. 



(3) 1847. Spirifer, Barrandb. Ueber die Brachiopoden der Silnr. Schicht. Bohmens. 



(1) 1852. Spirifer, Hall. Palajontology of N. Y., vol. ii, p. 66, pi. xxii, 2 d-s (not figs. 2 a-c, 2/) j 



p. 265, pi. liv, figs. 6 a-/. 



(2) 1852. Spirifer, Hall. Palaeontology of N. Y., vol. ii, p. 264, pi. liv, figs. 5a-f. 



(1) 1856. Spirifer, Billings. Canadian Naturalist and Geologist, vol. i, p. 135, pi. ii, figs. 2, 3. 



(2) 1856. Spirifer, Billings. Canadian Naturalist and Geologist, vol. i, p. 137, pi. ii, fig. 8. 



(1) 1859. Spirifer, Hall. Paleontology of N. Y., vol. iii, p. 202, pi. xxvii, figs. 1 a-f; pi. xxviii, 



figs. 8 a-d. 



(2) 1860. Spirifera, Emmons. Manual of Geology, p. 151. 

 (1) 1861. Spinfei-a, Hall. Ann. Rept. Geol. Survey of Wisconsin, p. 25. 



'S'j'm/era, Hall. Ann. Rept. Geol. Survey of 'Wisconsin, p. 26. 

 Spirifera, McChesnet;. Palaeozoic Fossils, p. 84. 

 Spirifera, Hall. Geol. Rept. Wisconsin, vol. i, p. 69, fig. 5 ; p. 436. 

 Spirifera, Hall. Geol. Rept. Wisconsin, vol. i, p. 69, fig. 6 ; p. 436. 

 •.The.parenthetical uumbers before the citations refer to the eabdivisions of the group. 



