300 EOCENE MOLLUSCA. 
No. 224. Pxreuroroma cepitta. F. #. Edwards. Tab. XXXI, fig. 5, a, 6. 
P. testa turritd, tuberculatd, undique transversim lineata: anfractibus convewiusculis, 
ad humeros obscure angulatis, plicatis ; postice concavis, tuberculato-marginatis ; ultimo an- 
Jractu antice in canal lato, breviusculo, terminato ; plicis numerosis, angustis, brevibus, ar. 
cuatis ; liners transversis regularibus; supra margines et humeros confertis, filiformibus, equa- 
libus ; ceterum crassioribus, distantioribus: aperturd oblongo-ovali ; labro aliformi, ad 
humerum late breviterque sinuato. 
Shell turreted, tuberculated, and concentrically lined ; the spire pointed, moderately 
elevated, barely equalling the aperture in length; the whorls, six or seven, exclusive 
of a small, conical pullus of two volutions, slightly convex, obscurely angulated on 
the shoulders, and armed with a row of rather numerous, short, curved, pliciform 
tubercles ; the posterior margins are slightly hollowed, and are thickened round the 
sutural edge, which is girt by a row of small, knob-like tubercles, not very distant from 
each other ; the last whorl is much contracted in front, and produced into a rather wide 
and short but distinct, and oblique, canal, notched at the anterior extremity. The 
transverse lines over the shoulders and posterior margins of the whorls are slender, 
depressed, regular, equal, and close-set ; those over the middle and front of the body 
whorl are coarser, and more distant, being separated by spaces as wide as themselves ; 
they are somewhat undulating, and are roughened by the lines of growth. The 
aperture is of an oblong-oval form; the outer lip wing-shaped, projecting at the 
middle, thin, sharp-edged, and smooth within; and the sinus, which is wide, not very 
deep, and almost semicircular, is placed on the shoulder. 
The present species is distinguished from P. rofel/a by the longer and more convex 
whorls, the short and curved folds on the shoulders, the wider and somewhat longer 
anterior canal, and the broader and shallower sinus. Like that species, it presents an 
analogy with P. xormalis (Desh., sp. ined.), but the wider and straighter posterior 
margins, with their simple sutural edge, and the more sharply angulated shoulders of 
the whorls, the more slender and regular concentrical lineation, and the marginal 
position of the sinus of the latter shell, render the two species easily separable. 
Size.—Axis, 6-12ths of an inch; diameter, rather less than 3-12ths of an inch. 
Localities —Barton and Alum Bay (Strat. No. 29, Prestw.), at both of which places 
it appears to be rare. 
