97 
with a rather deep linear suture. All the whorls of the spire are provided 
anteriorly with two snial] parallel carina; rather close to one another and 
serving as houndaries for the hand of the sinus ; the distance separating the 
anterior carina of this hand from the succeeding spiral whorl is equal to that 
between it and the posterior carina. The base of the shell is slightly convex, 
while the portion of the first, whorls of the spire that is visible is flattened . 
Tlie surface is ornamented with small rather mingled lines of growth, which 
have very little regularity. The aperture is sub-rhomboidal. The umbilicus 
appears to me to be free and very small. 
Dimensions. — Length, six millimetres ; diameter of the base, three 
and a half millimetres. 
]lelatio7is and Dl(ferences . — This species has very close analogy to 
P. conica, Phillips, from which it differs only in the lesser degree of the spiral 
angle, its small size, in the outline and little markedness of the lines of 
growth. 
Horizon and Localities . — -A single specimen has been seen in a block 
of limestone from the Yass District. 
Genus — EUOMPHALDS, Sowerby. 
1. EnoMPHALus NODULOsus, L. G. de Koninck. 
PI. I, Pig. 12. 
Shell small, sub-lenticular, strongly depressed, composed of six or 
seven spiral whorls, rapidly assuming a considerable width ; these whorls are 
enclosing and are separated from one another by a faint groove only. The 
surface is ornamented with a series of small transverse tubercles, sometimes 
a little sinuous, which are about twenty in number on the body whorl ; this 
being strongly set in a very hard and brittle calcareous rock, it is impossible 
for me to be sure of the shajie of the moutli and of the presence of an 
umbilicus. The spiral angle is about 150°, 
Dimensions . — Transverse diameter of the ])ase, fifteen millimetres. 
Relations and Differences. — Eiiomphalus tuherculatus, de Koninck, is 
in my opinion the species that resembles this one the most ; it differs in size, 
the much more rounded section of the spire, and the shape and prominence 
of the tubercles. 
