'DESCRIPTION OF SPECIES. 
191 
Tanged in lines', are only very slightly inclined from right to left, and 
the interspsces are about twice as wide as the prominences. The stri- 
ations are very slightly furrowed on top, but the edges are round and 
polished. 
The aperture is very large and open, measuring considerable more 
within than at the entrance. The lower tooth is proportionally short, 
being about .12 long, and is nothigh, about .04, and its position is cen- 
tral; the upper is situated about .10 above it, and is represented by a 
mere protuberance on the column. 
Margin not produced forward beyond the diameter of the shell, and 
is inclined very much to the left, far beyond the side, it is considerably 
thickened but becomes thinner on the edge, which is rolled backward 
considerably, producing a very flanging mouth, being in fact nearly bell- 
shaped. The frontal bar is not very prominent and the striations are 
not interrupted, indeed the whole interior of the shell is roughened with 
depressions which correspond to the external prominences. 
Color of shell externally, mixed white and pale chestnut, both col- 
ors being arranged in transverse zigzag markings that are often arro w- 
shaped. On the body of the shell the colors are in about equal parts, 
but on the back of the upper whirl, the white predominates, almost to 
the exclusion of the chestnut. Within, the color is pale orange, fading 
gradually into white on the outer portion of the margin. 
DIMENSIONS. 
Size of specimen figured, 1.58 by .57. Largest specimen, 1.75 by 
60; smallest, 1.25 by .45. Greatest diameter .60; smallest, .45. Long 
est specimen, 1.75; shortest, 1.25. 
