136 Trans. Acad. Sci. of St. Louis. 
than half the length of the shell. Length of a specimen having 4 body 
whorls, 7mm.; width, 2.7mm. Lower Claiborne Eocene of St. Maurice, 
Tig...-4 Boteitieis srieeie = wires dia cie nies p's sieielp aaieisigie a aicei es DAIWA EMRMELIED. 
11 — Spire elongate, gradually and evenly acuminate, about twice as long as 
the aperture and canal combined; beak gradually acuminate and straight 
from the abrupt contraction below the convexity of the body whorl; 
embryo of the Gemmula type, well developed, of two or three small smooth 
whorls followed by about three covered with arcuate riblets; spire whorls 
each witha strong subtumid subsutural collar which is fully as large and 
prominent as the obtusely crenulate and obscurely double, generally nar- 
row and feebly elevated peripheral carina, the latter distinctly below the 
middle; space below thiscarina with a single spiral carinule; space above 
it to the subsutural collar, broadly, evenly and rather feebly concave, 
with numerous very fine spiral threads; peripheral crenulations of the 
body whorl apparently rather less distinct; they become constantly 
longer in a spiral sense from one whorl to the next below. Length ofa 
specimen having 6 body whorls, 14 mm.; width, 3.9 mm. Lower Clai- 
borne Eocene of Lisbon, Ala.....+.-+-.- Sipwieisisisisysieisioisieieisi ol ANCE MIS Ds 
12 — Crenulate periphery at, or only slightly below, the middle...........13 
Crenulate periphery at, orextremely near, the lower or anterior margin of 
the spire WHOLIS....cc secre rece cece rece cccrcressccscrsccssessveses veld 
13 — Crenulations of the periphery fine, apparently not more than a seventh 
or eighth as long as the whorl, becoming obsolete on the seventh or 
eighth body whorl; subsutural collar apparently present on the crenu- 
late younger whorls; embryo imperfect in the types. Length of a 
specimen of about 10 body whorls, 48 mm. Claiborne (ferruginous 
SANG). 220 vece cece cevecccccen vevevccsccsccces ovcevsoe oti termata Con. 
Crenulations coarse, becoming on the sixth body whorl large, low, tumes- 
cent rounded elevations, with no distinct principal carinae, the entire 
surface having rather close-set and equal fine spiral carinules; on the 
upper whorl! the crenulations are more abruptly formed and are crossed 
by about three rather coarser lines, but the periphery nowhere has 
the abruptly elevated form seen in rotaedens and allies; the periphery is 
distinctly below the middle of the whorl and not at the middle as it 
seems to be in alternata, and the crenulations are nearly a fourth as long 
as the whorl, about 18 in number; upper whorls with a distinct subsu- 
tural collar which disappears completely on the larger whorls; body 
whorl below the posterior end of the aperture having rather coarse lines 
separated by about three smaller close-set threads. Length of a 
specimen having 6 body whorls about 19 mm.; width, 5.6mm. Lower 
Claiborne Eocene of St. Maurice, La.............,--obsolescens n. sp. 
14 — Shell moderately stout, the spire gradually, evenly acuminate and but 
little longer than the aperture and canal combined; embryo much higher 
than wide, with numerous riblets as usual; spire whorls evenly sculp- 
tured throughout with coarser and single finer intermediate spiral lines, 
not interrupted in longitudinal succession by the obtusely and gradually 
elevated periphery which bears obtuse crenulations, the latter disap- 
pearing altogether on about the seventh whorl; surface broadly, feebly 
concave from the subbasal periphery to the suture above, the latter 
having no trace of subsutural collar even on the nepionic whorls. 
