108 ; GEOLOGY—FOSSILS. 
List and Description of Organic Remains collected during the Exploration of the Central Pacific 
Railroad line, by Dr. JAMES ScHrEL, 1853-54. 
Pl. , Fig. 1.—Fenestella. Branches slender, bifurcating, with two rows of pores; some- 
times but one row; intervals oval or oblong, with rounded angles, and variable in size. 
It occurs with Productus semireticulatus and Productus aequicostatus in the limestone on 
Willow creek. It might, perhaps, be referred to Fenest. patula of McCoy. 
BRACHIOPODA. 
Pl. , Fig. 2, a, b.—Terebratula subtilita. Hall, Stansbury's expedition to the Great Salt 
lake, 409 ; Pl. 4, Figs. 1, 2. Gibbous, obovoid, tha nearly equal; beak of the dorsal valve 
elevated, bicarved. pers ated at the apex, mesial depression from centre to front; surface 
marked with concentric striz and with faint, radiating striz 
Occurs with Productus splendens, onde siriatus (?) Phüloitó, in the carboniferous lime- 
stone about six miles west of Westport. In one specimen the radiating stris are very distinct. 
Pl. , Fig. 3.—Productus splendens. Norwood and Pratten. The Producti in the western 
States, 11; Pl. 1, Fig. 5. 
From the same limestone. 
Pl. ,Fig.4, a, b.—Productus aequicostatus. Shumard. Large, elongate, dorsal valve much 
elevated ; beak small, passing slightly beyond the cardinal border; surface covered by longitudi- 
nal ribs, which bifurcate near the beak, and then continue without further division to the front, 
the spaces between being occasionally supplied with new ribs. These ribs are slightly sinuous 
occasionally, but most of them are straight from their origin to their termination. 
Occurs with Fenestella and Productus semireticulatus in the limestone on Willow creek. I 
have adopted for this shell the name given toit by Dr. Shumard, who kindly furnished me 
with the above preliminary description from his manuscript on the paleontology of the State 
of Missouri. A fuller description, and a drawing of a better and more perfect specimen, will be 
found in his report. 
Pl. , Fig. 5.—Spirifer, (indet.) Most likely Sp. striatus, yet the specimen is too imperfect 
for description. 
Occurs with Terebratula subtilita in the limestone near Westport. 
CONCHIFERA., 
Pl. , Fig. 6.—Znoceramus, (indet.) The specimen is only a cast of inoceramus from a 
yellowish cretaceous limestone near Fort Atkinson. 
Pl. , Fig. 7.—Jnoceramus confertim-annulatus. Roemer, Kreide. Texas, 59. Transverse, 
ovate, depressed, with concentric ribs and strie; the spaces between the ribs hardly equal to 
their width, and marked with regular, equidistant, elevated lines. 
I got this inoceramus in Salt Lake City, as coming from the Upper Green River batons It 
belongs to the cretaceous period. 
Pl. , Fig. 8.—Jnoceramus pseudo-mytiloides. Inequivalved, elongated, with concentric ribs 
and rim: anterior part subtruncated; posterior part slightly compressed, with a wing-like 
extension of the posterior margin against which the striæ are bending. 
It occurs in a gray limestone west of Fort Atkinson. ‘The only difference between this shell 
and Inoc. mytiloides is the bending out of the stris. 
Pl. , Fig. 9.—Gryphea Pitcheri. Shell thick, expanded, distinctly lobed, lower valve 
convex, upper valve thick and subconvex ; beak distinctly incurved. (Morton.) 
It was found on the top of a sand-hill near Grand river, where it occurs in great abundance, 
together with impressions of an ammonites. I am indebted for the determination of this shell 
to Professor Hall, who has several beautiful specimens in his collection. 
