43 
PILEOLUS plicatus; 
TAB. CCCCXXXII- -fig. 1 to 4 . 
Spec. Char. Obtusely conical, with diverging 
ridges extending to the edge; margin 
irregularly crenated ; the centre of the base 
divided. 
Syn. Pileolus plicatus, G. JB. Sowerbys Genera . 
There is an elevated margin to the flat cushion like 
centre of this species, and this centre is moreover di- 
vided into two parts by a slight sulcus that does not oc- 
cur in the following ; the height is not much less than 
the diameter of the base ; the inner lip is strongly 
crenulated. 
Found along with the following, but rare. Fig. 4, is 
magnified. 
PILEOLUS laevis. 
TAB. CCCCXXX1I .—Jig. 5 to 8, 
Spec. Char. Shell rather flat, smooth, with an 
entire margin. 
Syn. Pileolus Isevis, G* JB. Sowerbys Genera 
]V[ore depressed in form than the preceding ; the cen- 
tral portion of the base is convex, not circumscribed 
with a margin, nor divided as in P. plicatus ; the inner 
lip is obscurely crenated ; the upper surface is nearly 
smooth in general, but sometimes it has irregular indis- 
tinct furrows ; in a word, the general plainness and flat- 
ness of its contour distinguishes it from the P. plieatus 3 
Fig. 8 is a magnified representation. 
