890 THE PALEONTOLOGY OF MINNESOTA. 
(Bucania rugatina. 
Formation and locality—Trenton group (Middle Nashville), DeKalb county. Tennessee. A small 
imperfect specimen, possibly of this or the next species, occurred in the Clitambonites bed near Cannon 
Falls, Minnesota. 
Collections.—Prof. J. M. Safford; E. O. Ulrich. 
Bucania RUGATINA, n. sp. ( Ulrich.) 
PLATE LXVI, FIGS. 13—15. 
Resembles B. lindsleyi closely, but is smaller, the hight of what appears to be a 
full-grown individual being a trifle less than 20 mm. Of other differences we may 
mention that the whorls are more tightly enrolled, causing the umbilicus to be 
appreciably smaller, the transverse markings are relatively stronger, more equidis- 
tant, closer, averaging 1 mm. apart and appear more like waves or wrinkles than 
overlapping plates. <A. slight groove on each side of the slit-band occurs on the 
specimen illustrated. The other specimens are not in condition to permit us to 
decide whether these grooves are characteristic of the species or not. At any rate 
nothing of the kind has been observed on good specimens of B. lindsleyi. 
Formation and locality—Upper part of Trenton group, near Burgin, Kentucky, 
Collection.—B. O. Ulrich. 
BucaNIA NASHVILLENSIS, ”. sp. (Ulrich.) 
PLATE LXVI, FIGS. 86—40. 
This species is based on six specimens received from Prof. J. M. Safford and 
supposed by him to belong to his species Jindsleyi. A careful comparison with the 
original type of that species, good figures of which are given on plate LXVI, proves 
that they represent a closely related yet distinct species. In the first place the 
volutions expand more rapidly, two and a half turns making as large a shell as 
three whorls in the lindsleyi. Next the umbilicus is smaller and more abrupt, the 
sides of the volutions being more sharply rounded. Again the dorsum is more 
prominent along the central line, causing a more or less decided flattening of the 
dorso-lateral slopes. The slit-band also, instead of being sunken, is slightly raised. 
Finally, as regards the surface markings, the transverse lines are much less regular, 
and crowded rather than distant, while as a rule they would scarcely be described 
as lamellose. They are also much less distinct except near the aperture of large 
specimens where they are strengthened and emphasized, as usual with old shells, by 
irregular wrinkles. The oblique revolving lines also are little more than half as 
strong, while in the umbilical cavities, where these lines are usually very conspicu- 
ous in Safford’s species, they are scarcely distinguishable. After adding to these 
differences that the shell of B. nashvillensis is thicker, we believe we have given 
ample reasons for the creation of a new species. 
