328 Transactions.— Geology. 
` Clathurella rudis. 
Shell fusiform. Whorls 7, convex, with large, rounded, longitudinal 
ribs, which are broader than the interstices; there are 9 on a whorl, rising 
abruptly at the posterior end and dying away anteriorly ; those of the body 
whorl scarcely reaching half its length. Spiral ribs weak, about as broad 
as the interstices, 9 on the spire whorls and 20-25 on the body whorl. Aper- 
ture ovate, produced into a short anterior canal. 
Length, 48 inch ; breadth, -22 inch. Aperture, :22 inch. 
Locality. Waihao, in green-sand. 
Clathurella leptosoma. 
Shell small, elongato-fusiform, the spire produced and acute. Whorls 
6-7, the first two smooth, the third spirally striated, the others longitu- 
dinally ribbed and spirally striated; all the whorls after the third slightly 
angled. On the body whorl the longitudinal ribs are obsolete ; spire 
whorls with two strong spiral strie and other smaller ones; body whorl 
with the two strong spiral strie followed by about 20 small ones, regular 
and equidistant. Aperture narrow, angled behind, produced anteriorly into 
a short canal. 
Length, :25 inch ; breadth, -08 inch. 
Locality. White Rock River. 
Clathurella incisa. 
Shell fusiform. Whorls 6-7, rounded, the first two embryonic, the 
others longitudinally plicated and strongly spirally ribbed. Longitudinal 
plications 16 in a whorl; spiral ribs 9 on the penultimate, and 18 on the 
body whorl ; posterior spiral ribs about their own breadth apart, but the 
four anterior ones on the body whorl further apart. Aperture ovate, pro- 
duced into a short anterior canal. 
Length, ‘8 inch ; breadth, -42 inch. 
Locality. Te Aute, Hawke’s Bay. Collected by Mr. A. Hamilton. 
Spiral ribs much stronger than in C. hamiltoni. 
Cassis senex. 
Struthiolaria senex, Hutton, Cat. Tert. Moll. of EZ p iL 
rpura excursa, Hutton, Lc., p. 6 (1873). 
An excellent specimen from Pareora shows that this species is a Cassis. 
The inner lip has a large callus and is slightly rugose in front. The whole 
shell is finely spirally striated, and there is sometimes a third row of 
nodules on the body whorl. There are 12-17 nodules in a row on each 
whorl. 
Cerithium bicorona. 
Shell subulate, Whorls flattened, spirally striated, the posterior half 
With two rows of longitudinally elongated nodules, of which there are about 
