218 PALEONTOLOGY OF THE EUREKA DISTRICT. 
the exfoliation of the shell has destroyed any finer striz that may have 
existed. 
This is essentially a Devonian type, approaching such forms as Spiri- 
fera Marcyi, S. macronata (Pal. N. Y., vol. iv), in their dorsal valves; unfor- 
tunately there are no specimens of the ventral valve in the collections. 
Formation and locality.—Lower portion of the Lower Carboniferous 
limestone in canon directly south of a small conical hill on east side of 
Secret-canon-road Cation, Eureka District, Nevada. 
Subgenus SPIRIFERINA D’Orbigny. 
Spiriferina cristata Schlotheim. 
Plate xviii, figs. 12, 13. 
Terebratulites cristatus Schlotheim, 1816. Beitr. z. Naturg. d. verst. in Akademie der 
Weissenschaften zu Miinchen, pl. i, fig. 3. 
Spirifera octoplicatus Sowerby, 1827. Min. Con., p. 120, pl. 562, tables 2, 4, 4. 
Spirifer cctoplicata? Hall, 1852. Stansbury’s Expd. Great Salt Lake, p. 409, pl. iv, 
figs. 4a, b. (Not S. octoplicatus Sowerby.) 
Kentuckensis Shumard, 1855. Geol. Surv. Missouri, vol. i, pt. 2, p. 208. 
Kentuckensis Hall, 1856. Pacific Railroad Rep., vol. iii, p. 102, pl. ii; figs. 10, 
11. 
spinosus Norwood & Pratten, 1855. Jour. Acad. Nat. Sci. Philad., vol. iii, p. 
71, pl. ix, figs. la-d. 
spinosus Hall, 1858. Geol. Surv. Iowa, vol. i, pt. 2, p. 706, pl. xxvii, figs. 5a-c. 
Spiriferina octoplicata Davidson, 1852. Quart. Jour. Geol. Soe, London, vol. xviii, p. 
29, pl. i, figs. 12-13: ~ 
Spirifera Kentuckensis var. propatulus Shumard, 1866. Trans. St. Louis Acad. Sci., 
vol. ii, p. 409. 
laminosus Geinitz, 1866. Carb. und Dyas in Nebraska, p. 45. (Not S. lami- 
nosus McCoy.) 
Spiriferina Kentuckensis Meek, 1872. U.S. Geol. Surv. Nebraska, p. 189, pl. vi, figs. 
3a-d; pl. viii, figs. 11a, b. 
spinosa ? Derby, 1874. Bull. Cornell University, vol. i, pt. 2, p. 23, pl. vi, 
figs. 8, 13, 14. 
Kentuckensis White, 1875. Expl. and Surv. West 100th Meridian, vol. iv, 
pt. 1, p. 138, pl. x, figs. 4a—c. 
Characteristic specimens of this species occur in the lower and central 
portions of the Carboniferous rocks of the district, and in the upper strata 
they are associated with a form that is typical of S. spinosa, of the Chester 
limestone of Illinois. This same association also occurs at Coal Hill, in the 
