178 
MONOGRAPH OP TI1E GENUS STHOPHIA. 
back, nearly twice its length fi\m the frontal bar. A ridge 
extends from tooth to the third whirl Upper tooth absent. 
Margin produced forward about as far as the diameter of the shell, 
is placed very nearly in the centre of the shell and is not inclined to 
the right, is about twice as thick as the 
shell behind it, is smoothly rounded on Fig. 59. 
the edge and rolled over into a rather 
sharp edge. The frontal bar is not 
well-developed and does not cross the 
shell, being broken in the middle, 
hence does not completely interrupt 
the striations, which appear within it. 
Color of shell, externally, white, 
beautifully marked with longitudinal 
and rather continuous streaks of dark 
reddish brown. Internally, far within 
the shell, pale brown becoming white 
on the entire margin, tooth, and space 
around it, with a slight creamy tinge. 
jW Kiuii ita. 
WjsO; LiH.auM 
Stroj hia eximea. 
of type. 
A, front, B, Bide view 
DIMENSIONS. 
Size of type, 1.12 by .45. Largest specimen, 1.12 by .47 ; small- 
est, .75 by .37. Greatest diameter, .47 ; smallest, .37. Longest 
specimen, 1.30; shortest, .97. 
OBSERVATIONS. 
There is considerable individual variation, one is toward a cylin- 
drical form with even more numerous striations, sixty to the first 
whirl, with a contracted aperture, and eleven whirls. A color variation 
is a paler form with rather narrow markings, which are also paler. 
There is a tendency to produce a form with an entire frontal bar. 
There is also the following well-defined form : 
No. 1. Size, very small. Whirls, nine. Color, form and 
striations as in the typical form. 
This is not the Pupa martensiana of Weinland for in that species 
the teeth are given as two and the margin as being thick. S. eximea 
may be distinguished from all other shells of this sub-genus by the 
large size, in the type form, and always by the dark, wide longitudinal 
markings. 
