1903.] STANTON—MOLLUSCAN FAUNULE. 197 
There are seventeen other less perfect specimens in the collec- 
tion, all of which agree fairly well with the type so far as their 
characteristics are preserved. 
This species is very closely related to Campeloma macrospira 
Meek,’ and may prove to be not more than a variety of that species 
from the Bear River formation in western Wyoming. Compari- 
son of C. harlowtonensts with the type and with a large suite of 
specimens from the same horizon in Wyoming show that Meek’s 
species averages considerably smaller, and that it is somewhat more 
slender, with the sutures slightly more oblique and the last whorl 
relatively larger. The last-named peculiarities cause a greater 
difference in the aspect and proportions of the shells than would be 
indicated by measurements. There are also differences in the form 
of theinner lip. There are, however, associated with the typical 
form of C. macrospira a few specimens that approach more closely 
to the form here described, and this fact suggests the question 
whether there are really two species, or only varieties of one 
variable species. 
Locality.—Wettacombe’s ranch, near Musselshell River, in the 
vicinity of Harlowton, Montana. 
Hforizon.—Upper part of Lower Cretaceous or base of Upper 
Cretaceous. 
GONIOBASIS? ORTMANNI n. sp. Pl. IV, Figs. 7-10. 
Shell small, moderately slender, consisting of about six convex 
whorls ; aperture elongate ovate, slightly produced below; inner 
lip somewhat thickened, closely appressed to last whorl above, 
slightly reflexed below so as to partly cover the small umbilical 
chink ; surface bearing inconspicuous growth-lines, usually crossed 
by a variable number of much more prominent sharply elevated 
spiral lines, which in some cases are strong enough to be called 
small carinz. Specimens which may be considered to have the 
average or typical sculpture show four spiral lines on the whorls of 
the spire, with about six additional on the base of the last whorl 
1 Named by Meek in a list without description in Regt. U. S. Geol, Surv. 
Zerr., for 1872, p. 478. Described in 1877, U. S. Geol. Expl. 40th Parallel, 
Vol. IV, pt. 1, p. 180, with figures of a small shell doubtfully referred to the 
species. Figures of Meek’s original type are published by White, Zwel/th 
Ann. Rept. U, S. Geol. Surv. Terr., Pl. 30, Fig. 2a; Third Ann. Refi. VU. S. 
Geol. Surv., Pl. 8, Figs. 6,7, and Bull. U. S. Geol. Surv., No. 128, Pl. 10, 
Figs. 2, 3. 
