976 THE PALEONTOLOGY OF MINNESOTA. 
[Lophospira conoidea. 
This species, considering that it is a close ally of L. perangulata and L. elevata, 
and therefore an undoubted Lophospira, is remarkable for the great elevation of 
the spire. It reminds decidedly of L. bowdeni Safford sp., but has a larger umbilicus, 
more angular volutions and a well developed Jower carina, a feature that is scarcely 
distinguishable in that species. In our opinion L. producta has been developed from 
L. perangulata, while L. bowdeni probably had its origin in L. owent. 
Formation and locality.—Upper Trenton, Nashville, Tennessee. 
Collection.—E. O. Ulrich. 
LopHosrira conorpKA, n. sp. (Ulrich.) 
PLATE LXXIII, FIG. 22. 
Hight about 40 mm.; apical angle 42°. Volutions about six, somewhat loosely 
coiled. Peripheral carina prominent, situated very low.for the genus, just above 
the deep suture, the edge thick and flat rather than round. An angulation about 
the middle of the under side of the last whorl surrounds a slight depression which 
farther inward sinks rather suddenly into a deep umbilicus. Upper slope slightly 
concave in the lower half, convex in the upper. Lines of growth sweeping strongly 
backward to the peripheral band, consisting without regularity of stronger and 
weaker striz. 
This species is remarkable for the low position of the peripheral band. In this 
it has gone a step farther than L. producta, which we believe connects it with L. 
decursa and through that with L. perangulata. 
Formation and locality —The type specimen was found by Prof. J. M. Safford in the Trenton group 
at Nashville, Tennessee. 
LoPHOosPIRA PERACUTA, 7. Sp. 
PLATE LXXIII, FIGS. 15—17, 
Hight 25 to 40 mm.; apical angle 58°. Volutions five or six; peripheral band 
rather sharp and very prominent; upper surface of volutions gently concave to the 
suture, without a trace of the carina; lower carina wanting; umbilicus small, 
aperture rounded below and upon the inner side; surface markings obscure, curving 
backward strongly. 
In this species the peripheral angle is sharper and more prominent than in any 
other known to us. The mouth is shorter and rounder upon the inner side and the 
volutions project over each other in a greater degree than in L. oweni. The shell 
is much larger, and the peripheral angle more prominent than in L. perangulata. 
That species differs further in having a lower carina. JZ. ampla has a wider apical 
angle, a subsutural carina, and a differently shaped aperture. In L. swmnerensis 
