148 PALEONTOLOGY OF THE EUREKA DISTRICT. 
Genus ATHYRIS McCoy. 
Athyris Angelica Hall. 
Athyris angelica Hall, 1861. Fourteenth Ann. Rep. N. Y. State Cab. Nat. Hist., p. 99. 
Hall, 1867. Pal. N. Y., vol. iv, p. 292, pl. xlvii, figs. 9-20. 
This species, in New York, is known only in the Chemung Group, a 
horizon comparable with the upper beds of the Devonian of the Eureka 
District, although the fauna is not as specialized as in the East. In all essen- 
tial particulars the specimens from these widely separated localities are 
specifically identical, with the exception of one feature, which has not been 
observed in the New York examples. When the outer part of the shell, 
with the imbricating lamellze or lamelliform striz is exfoliated, the entire 
surface is more or less marked by radiating strize. The form of the shell 
varies, as in the New York specimens, from transverse to elongate, the latter 
usually prevailing. 
Formation and localities —Devonian limestone, The Gate, northwest of 
Eureka, and Newark Mountain, Eureka District, Nevada. 
Athyris (sp. undt.). 
A single specimen of this fornt with the shell exfoliated, except on the 
upper portion, occurs at Lone Mountain, low in the Devonian. It resem- 
bles Athyris cora, of the Hamilton and Chemung Groups of New York (Pal. 
N. Y., vol. iv, 291, pl. xlvii, figs. 1-7), but is probably a distinct species. 
Genus MERISTELLA Hall. 
Genus WHITFIELDIA Davidson. 
Meristella (Whitfieldia) nasuta Conrad (Sp.) 
Plate iii, figs. 8, 8a, 8b. 
Atrypa nasuta Conrad, 1842. Jour. Acad. Nat. Sci. Philad., vol. viii, p. 265, figs. 8, 9. 
Meristella nasuta Hall, 1860. Thirteenth Ann. Rep. N. Y. State Cab. Nat. Hist., p. 93. 
elissa Hall, 1861. Fourteenth Ann. Rep. N. Y. State Cab, Nat. Hist., p. 100. 
Tbid., 1862. Fifteenth Ann. Rep., pl. iii, figs. 21, 22. 
nasuta Hall, 1862. Fifteenth Ann. Rep. N. Y. State Cab. Nat. Hist., p. 160, 
figs. 17-19 of p. 161. 
