138 PALEONTOLOGY OF THE EUREKA DISTRICT. 
Spirifera Englemanni Meek. 
Spirifera Englemanni Meek, 1860. Proc. Acad. Nat. Sci. Philad., vol. xii, p. 308. 
Meek, 1876. Rep. Expl. Great Basin of Utah (Simpson), p. 346, 
pl. i, figs. la-e. (Not S. Englemanni, M. & W.) 
Meek, 1877. Rep. Geol. Expl. Fortieth Par., vol. iv, p. 41, pl. 
ili, figs. 3a-e. 
The original specimens of this species were found at The Gate, north- 
west of Eureka, by Colonel Simpson’s exploring party, and subsequently 
Mr. Arnold Hague obtained examples from the White Pine Mountains south- 
east of the Eureka District. 
The specimens in the present collection came from Newark Mountain, 
in the upper portion of the Devonian limestone, and present the essential 
characters given by Mr. Meek in his description of the species. 
Spirifera Pinonensis Meek. 
Plate iv, figs. 1, la-f. 
Spirifer (Trigonotreta) Pinonensis Meek, 1870. Proc. Acad. Nat. Sci. Philad., vol. xxii, 
p. 60. Ibid., 1877, Geol. Expl. Fortieth Par., vol. iv, p. 45, pl. i, figs. 9a, b. 
Spirifera (Trigonotreta) argentarius Meek, 1877. Geol. Expl. Fortieth Par., vol. iv, p. 
42, pl. iv, figs. 4 a—b. 
This species ranges from the base to the summit of the Devonian 
limestone, throughout the Eureka District, and also occurs in the Pinon 
Mountains, where the original types described by Mr. Meek were collected. 
In the White Pine Mountains the variety described as S. (7.) argentarius 
Meek is found in the Middle and Upper Devonian. The species S. Pino- 
nensis was founded on the larger, more coarsely ribbed variety. Among 
the large series collected in the Pinon Range a shading off into the smaller, 
finer ribbed form is observed, and among the still more extensive series from 
the Eureka District the gradation of form and characters between the type 
of S. Pinonensis and P. argentarius is complete. 
Formation and localities —The species ranges throughout the Devonian 
limestone, having been found in the upper beds south of The Gate and at 
Newark Mountain; at the lower horizon it occurs at Comb’s Peak; Atrypa 
Peak; Lone Mountain, 18 miles northwest of Eureka, ete., Eureka District; 
also at the west base of Mount Argyle, White Pine District, Nevada. 
