MONOGRAPH OF THE GENUS STROPIIIA. 
STROPHIA SCRIPTA OBLITERATA Novo. 
Pale Strophia. 
Plate I, fig. 5, front, fig. 6, side view of type. 
DESCRIPTION. 
Sub Sp. Oh. Size, small, shell, rather thick and heavy, striations 
present, whirls, 10, examined 102 specimens. 
Form of shell, a pointed cylinder with the first whirl the largest, 
the second, third and fourth are successively a little smaller, then the 
shell tapers to a rather obtuse point, forming an angle of about sixty- 
three degrees. The striations are few, fifteen to the first whirl. They 
are quite prominent, rather irregular, quite straight, hut not arranged 
in lines. They are not furrowed, but are smoothly rounded and 
polished. 
Aperture, rather small, slightly contracted within. Roth teeth 
are represented by a mere tubercle. 
Margin produced forward about as far as the diameter of the 
shell and is scarcely inclined to the right. The margin is only slightly 
flanging and is not rolled over, while the edge is slightly rounded. The 
frontal bar is quite well developed, but the striations appear within it 
as quite prominent ridges which extend into the shell quite to the apex , 
as shown in a sectionized specimen. 
Color of shell, ashy white externally, rather sparingly marked 
with longitudinal patches of inconspicuous pale reddish brown. These 
patches are frequently broken into transverse lines by the encroachment 
of the white. Within, yellowish brown which becomes paler on the 
margin. 
DIMENSIONS. 
Size of type 1.08 by .40. Longest specimen, 1.13 by .43. Small- 
est 1.00 by .30. Greatest diameter .43, smallest, .30. Longest specimen, 
1.13, shortest, 1.00. 
OBSERVATIONS. 
There appear to be a number of quite distinct forms. 
No. 1 is without markings, being pure white, and as is usual in 
similar cases, where a white form has become evolved from a colored 
one, the shell is thinner, with a consequent less development of frontal 
bar. The average size is a little smaller, but the form is similar. 
There are about ten per cent of this form. 
No 2. Smaller than the type, proportionately stouter, with nine 
whirls, otherwise similar. There are about seventy per cent of this 
form in the collection, but as the form described as typical, approaches 
