986 THE PALEONTOLOGY OF MINNESOTA. 
(Lophospira bowdeni. 
concave to the prominent peripheral band; base at first a little concave because of 
a low ridge a short distance beneath the band, then following the course of the 
striz, with a concave outline to the acute basal extremity; umbilicus very small; 
inner lip nearly vertical, twisted, and greatly produced below. Surface markings 
very faint upon the upper side of the volutions; on the base they consist of rather 
regular, strong, overlapping lamelle, curving strongly forward from the peripheral 
band and, finally, running in a nearly vertical direction, and almost parallel with 
the inner lip, to the narrow basal extremity of the aperture. 
There is no described species (of this family) known to us having the aperture 
produced below as much or in the same manner as in this shell. A similar condition 
is exhibited by two specimens from the Lorraine group, one from Cincinnati, the 
other from central Kentucky, but as the apical angle is somewhat less in these (56° 
and 57°) and the lower side of the volutions more ventricose, we hesitate to say that 
they belong to the same species. The surface being abraded on them we cannot 
say how the markings compare with those observed on the type described and figured. 
Formation and locality.—Richmond group of the Cincinnati period, Hanover, Butler county, Ohio. 
Collection.—E. O. Ulrich. 
LopHospiRa BOWDENI Safford. 
PLATE LXXII, FIGS. 40—43. 
Murchisonia bowdeni SAFFORD, 1869, Geol. of Tenn., pl. a, figs. 2a-2c. (Not described.) 
Hight 40 to 70 mm., usually 45 to 50 mm.; apical angle of Tennessee types of 
species averaging about 27° but varying between the extremes of 26° and 30°; of the 
Lorraine group variety 30° to 34°; of the Richmond group form 25° to 28° for 
specimens from Trimble county, Kentucky, and 27° to 83° for those from Boyle 
county in the same state; volutions eight to ten, moderately angular, the peripheral 
band thick, convex, varying as to prominence, situated beneath the center of the 
whorls; upper slope convex, sometimes obscurely carinated, in the upper half, more 
or less concave in the lower half; lower carina obscure, never sharp, often indistin- 
guishable, the space above it to the peripheral carina generally a little concave; a 
minute umbilicus usually present, though in narrow specimens it is commonly 
covered by the reflexed inner lip; aperture subtriangular or irregularly quadrate, 
the outline depending upon the angle at which it is viewed; inner lip nearly vertical, 
generally exhibiting a small channel in its lower part. Surface with obscure 
undulations or unequal lines of growth. Th se are very strongly recurved toward 
the peripheral band, indicating a large and deep >shaped notch in the outer lip’ 
The band is distinctly convex, occasionally subangular in the middle, has obscure 
lunul, and is bordered on both sides by a delicate raised line. 
