92 GEOLOGICAL SURVEY OF THE TERRITORIES. 
by an effort to form three, or rarely four, obscure revolving lines or ridges, 
the upper of which is larger and more prominent than the others, which 
character, with the slightly enlarged upper ends of the vertical coste, 
causes the thickened appearance of the upper margins of the volutions; 
several other slender and more distinct revolving lines also occur on the 
under side of the last turn. Aperture somewhat rhombic-ovate. 
‘Length, about .60 inch; breadth, .18 inch.” 
This shell is plainly related to G. cleburni, with which it is associated, 
but its comparatively minute size and the details of its form show dif- 
ferences too great to require detailed comparison. 
It has been found in considerable numbers in the Bear River Laramie 
series, near the mouth of Sulphur Creek, Bear River Valley, Wyoming; 
where it is associated with many other species, including those which 
are most characteristic of the series. 
GONLOBASIS CHRYSALLOIDEA White. 
Plate 30, figs. 5 a and 6. 
Goniobasis chrysalloidea White, 1876, Powell’s Rep. Geol. Uinta Mts., p. 123. 
Shell of medium size, gradually tapering from the last volution to the 
apex; volutions about seven or eight, those of the spire slightly con- 
vex, the last one broadly rounded to the anterior end; suture impressed, 
the apparent impression being increased by the projecting fold of the 
distal border of each volution, which is appressed. against the next pre- 
ceding one. Surface marked by more or less distinct longitudinal, 
slightly-bent ridges or varices, which are crossed by several revolving 
lines that appear only on the ridges, and not between them, giving the 
ridges a knotted or crenulated appearance; anterior surface of the last 
volution also marked by distinct raised revolving lines. 
Length, 28 millimeters ; diameter of the last volution, 9 millimeters. 
This species is closely related to both G. cleburni and G. chrysallis, 
with both of which forms it is associated. It differs from the latter in its 
much larger size, much greater apical angle, straighter sides of the spire, 
and in the details of its ornamentation. It differs from G. cleburni in its 
smaller size, the more distinct crenulation of its longitudinal varices or 
folds, and in possessing the revolving fold-like projection of the distal 
border of its volutions. 
Position and locality——Bear River series of the Laramie Group, near 
the mouth of Sulphur Creek, Bear River Valley, Wyoming. 
GONIOBASIS ENDLICHI White. 
Plate 30, figs. 7 a, b, and ¢. y 
Goniobasis endlicht White, 1878, Bull. U. S. Geol. Sur. Terr., vol. iv., p. 716. 
Shell moderately elongate-conical; spire with straight or slightly 
concave sides; volutions six or seven, much, and nearly regularly, con- 
vex, the last one slightly inflated ; suture well defined, and appearing 
unusually deep on account of the convexity of the volutions; aperture 
subovate in outline, its distal end angular, its front somewhat narrowly 
rounded and without a sinus; outer lip apparently sharp; inner lip 
with a thin reflected callus, which is more developed anteriorly than 
posteriorly ; columella gently arcuate. . 
Surface marked by fine but distinct lines of growth, which are crossed 
by very numerous fine, revolving, raised lines, giving it a cancellated 
