MONOGRAPH OF THE GENUS STROPHIA. 
69 
13. STROPHIA IANTHINA Novo. 
Violaceous Strophia. 
Plate II, 13 & 13a, shell. 
DESCRIPTION. 
Sp. Ch. Size, medium. Shell, rather heavy and elongated, the 
width being about one third the length. Striations, present. Teeth, 
two, both short and not prominent. Whirls, 11. Examined 300 spec- 
imens. 
Form of shell, cylindrical, the first three whirls being nearly equal 
in diameter and occupy more than two thirds of the length of the shell. 
The fourth whirl is but slightly smaller and from this, the shell tapers 
to a blunt point, forming an angle of 65 degrees. The striations are 
numerous, 24 on the upper whirl; they are prominent, very regular, and 
arranged in lines which are quite straight, being very little inclined 
from right to left; and the interspaces are little wider than the promi- 
nences. The striations are not furrowed and the edges are smooth and 
rounded. 
Aperture, very large and open, measuring considerably more just 
within than at the entrance. Lower tooth very small, .02 high and .08 
long, placed about in the centre, and the upper tooth is but a mere 
rudiment. 
Margin, not produced forward beyond the diameter of the shell, 
slightly inclined to the right, is thin, with the edge rolled well back, 
about once the thickness of the margin. The frontal bar is well devel- 
oped and the striations appear within elevated. 
Color of shell externally, deep violaceous purple, gradually becom- 
ing reddish orange toward the apex which is nearly white. The margin, 
frontal bar and striations are white, the latter somewhat encroached up- 
on, especially above, by violaceous. Internally, very deep, rich purplish 
brown. 
DIMENSIONS. 
Size of types; 1.15 by .37 and 1.00 by .36. Largest specimen, 1.15 
by .42; smallest, .85 by .30. Greatest diameter, .42, smallest, .30. Long- 
est specimen, 1.15; shortest, .85. 
OBSERVATIONS. 
The type form prevails but there is a tendency toward a smaller 
form with finer striations, but these specimens are possibly only rever- 
sions toward some of the several finely striated species that occur on 
Inagua. Distinguished at once from all others, by the deep purplish 
