62 
Aug. F. Foerste 
apical end, about as large as in the specimen here figured, almost 
touches the dorsal side of the aperture; but on account of its poor 
state of preservation it cannot be definitely identified with the 
present species; the distance between the septa is slightly greater. 
Annular costae distinct at all stages of growth preserved by the 
type specimen, deflected toward the apical end; along the sides ] 
of the shell, between the dorsal part and the ventro-lateral angle, | 
the curvature of costae is fairly constant, but at the ventro-lateral I 
angle the costae are deflected more rapidly toward the apical end I 
of the shell, forming a sinuate curve along the median part of the i 
ventral side. Shell distinctly compressed laterally, the ventro- | 
dorsal diameter of the larger end of the living chamber of the | 
smaller fragment figured being 16.5 mm., and the lateral diameter | 
12.3. The costae are more prominent at the ventro-lateral angles, | 
adding to the flattened appearance of the sides and producing also ' 
a slightly flattened appearance along the ventral face. Along the 
median part of the ventral face the costae form a deeper and more 
angulate sinus than do the costae of Cyrtoceras rigtdum\ the shell 
is narrower, and the greater prominence of the costae at the ventro- 
lateral angles is a distinguishing feature. Siphuncle ventrad of 
the center, about .7 of the distance from the dorsal to the ventral 
side, poorly preserved, apparently narrow and tubular. Septa 15 
in a length of 50 mm. in the type specimen figured, the distance 
between the septa being greater during the ephebic stage. Internal 
casts of the shell and such parts of the shell as are preserved show 
faint transverse striations, about 30 to 35 in a length of 5 mm.; 
these striations are transverse to the length of the shell and main- 
tain their directions across the costae. In one weathered specimen 
there are faint traces of longitudinal striae, but in all other speci- 
mens only transverse striae are seen. 
Osgood bed: Clifton, Tennessee. 
Hyolithus cliftonensis, sp. nov. 
{Plate III, Figs. s8 A, B.) 
Length of more complete specimen, 32 mm.; original length 
possibly 38 mm.; width at the larger end, 12 mm.; width 26 mm. 
from the larger end, 6 mm.; vertical diameter at right angles to the 
width at the larger end, 8 mm. Dorsal side strongly convex, but 
flattened sufficiently on each side of the strongly rounded median 
