MONOGRAPH OF THE GENUS STROPHIA. 
129 
DESCRIPTION. 
Sp. Ch. Size, rather large. Shell, heavy. Striations, present. 
Whirls, 10. Teeth, two, the upper inconspicuous, the lower extremely 
long and channeled. Examined 25 specimens. 
Form of shell, cylindrical, with the first three whirls of the same 
diameter, the fourth is but little smaller, and from this the shell slopes 
to a rather blunt point,, forming an angle of 60 degrees. The sutures 
are very shallow, and the whirls between them bulge but little 
The striations are very numerous, 50 on the first whirl, are not 
arranged in lines, yet are quite regular; they are slightly inclined from 
right to left, and the interspaces are a little narrower than the promi- 
nences. The striations are rounded on top and polished. 
Aperture quite large and open, but narrows rather rapidly within. 
The lower tooth is not very prominent, but extending backward along 
the lower wall about .15, becomes widened and channeled, and in this 
form passes downward, terminating on the right side of the third whirl; 
its length is thus about .75! Its position is a little nearer the column 
which it encircles, than to the outer wall. (See Fig. 32, A, where is 
given a life size view of the upper portion of the tooth, the top of the 
shell having been removed; o, shows the tooth; c the frontal bar.) The 
upper tooth is a mere prominence, but gains in size as it passes back- 
ward, and makes a complete turnaround the column. 
The margin is not produced forward beyond the diameter of the 
shell, slopes slightly backward, and is a very little inclined to the right, 
is rather thick, measuring .06, and the edge is rolled slightly backward, 
but is not thin. Frontal bar, well developed, and the lower wall of the 
aperture within it is smooth, but the striations are slightly apparent 
beneath the enameling. 
Color of shell, externally, shining white, sparingly mottled with red- 
d c b 
