Casey — Notes on the Pleurotomidae. 7) 
Length of a, specimen of 8 body whorls, 32 mm.; width, 8.5 mm. 
Lower Claiborne Eocene, St. Maurice, La. ..........lndoviciana Vgn. 
15 —Costules of the peripheral raised band carried obliquely across the 
surface between the latter and the subsutural cariniform collar, gen- 
erally forming a distinct beading on the latter; spiral lines above the 
posterior end of the aperture very sparse and indistinctly defined, 
below the latter on the body whorl having the form of coarse con- 
spicuous and widely spaced lyrae, the concave intervals between the 
lyrae having many close-set striae. Length of a specimen having 6 
body whorls, 16.5 mm.; width, 4.9 mm. Upper Vicksburg Oligo- 
CONG cae wad Sate nod via cicias vaaswloe cee daaiahald cadets ald-ede TOMO CON, 
Costules not extending across the rather more deeply concave surface above 
the somewhat narrower and more strongly elevated peripheral band, 
the subsutural carina finer and almost even, not at all beaded, the con- 
cave surface with three or four close-set and distinctly defined spiral 
lines; body whorl below the periphery with coarse and widely spaced 
lyrae; shell similar in form to tenella buta little smaller. Red Bluff 
OCONEE oc 00 occ ece vec vecccces co seetes ceccce secs cove ccoess ANCA CS, 
Costules abruptly confined to the peripheral band as in ancilla, the subsu- 
tural collar very large, obtusely elevated and coarsely beaded, separated 
from the peripheral costulose band by a deep abrupt coneavity about equal 
in width to the raised band and bearing a fine and almost even median 
thread; space below the band with about two close-set and rather fine 
spirals which are moreor less nodulose; shell differing from the two pre- 
ceding in its smaller size, shorter and much stouter form and thicker 
substance, the embryo small and more rapidly pointed. Length of a 
specimen of 5 body whorls, 9.5mm.; width,3.6mm. Jacksonian Eocene 
of Moody’s Branch, Miss...6 0... .ccc.cees cece ceceess NOGUINAN. Sp. 
Lancea is a rather aberrant species in general features of 
sculpture but seems to belong to the present genus; it is rep- 
resented by a single rather water-worn specimen. The char- 
acters of aléernata are taken from a very careful drawing from 
the original type kindly lent me by Mr. Aldrich ; Conrad states 
that Jesueur?, of Lea, is identical, but the latter is a widely 
different species, having the anal sinus on the upper concave 
surface of the whorls.\ number of species, not alluded 
to above, are known, but not being able to study the types 
or any accurate drawings, Iam unable to include them at 
present; among these are P/. mediavia and equiseta, of 
Harris, and moniliata of Heilprin. 
It is desirable before discussing the genera of the Surcula 
type to draw attention to a succession of peculiar Indo-Pacific 
forms, resembling Plewrotoma in the absence of true ribbing 
and great development of the spiral carinae, but differing in 
