FOSSILS OF THE DEVONIAN. 191 
This and the preceding species have slight indications of uninterrupted 
concentric lines of growth, so that the generic reference will probably be 
sustained on the finding of more perfect specimens. They are large, robust 
forms, differing very much from each other and from any described species 
occuring at the same geologic horizon. 
Formation and locality.—Lower horizon of the Devonian limestone, 
Comb’s Mountain, Eureka District, Nevada. 
Loxonema ? subatteruatum Hall ? 
Loxonema subattenuata Hall, 1861. Descriptions of New Species of Fossils, ete., p. 24. 
Tdem., 1862. Fifteenth Ann. Rep. N. Y. State Cab. Nat. Hist., p. 52. Idem., 
1876. Pal. N. Y., Illustrations of Devonian Fossils, Gasteropoda, pl. xiii, 
figs. 1-3. Idem., 1879. Pal. N. Y., vol. v, pt. 2, p. 40, pl. xiii, figs. 1-6. 
The illustrations of this species in the Paleontology of New York do 
not show the surface characters, which restricts the comparison to the casts; 
among these the differences between the two, L. subattenuatum and the Ne- 
vada form, are so slight as to make it impossible to separate them on good 
specific characters. 
The species occurs at Comb’s Peak, in the Lower Devonian, and at the 
same relative horizon in Gray’s Canon, Kureka District, Nevada. 
Loxonema approximatum, n. sp. 
Plate vi, fig. 7. 
Shell, terebriform; spire rapidly ascending, volutions slightly convex, 
increasing regularly from the apex, the last one a little vertical; six in the 
length of 24 inches from the base. Aperture subelliptical. 
Surface as shown on the inner cast, marked by moderately strong, not 
closely arranged, longitudinal striz that are nearly transverse to the volu- 
tions; the striz arch backward very slightly. 
The description of this species is nearly identical with that of Loxone- 
ma styliola Hall (Pal. N. Y., vol. v, pt. 2, p 48, pl. xiv, figs. 8, 9) from the 
Chemung Group of New York. It differs only in the more elongate form 
