APPENDIX—MOLLUSCA. 557 
This species is most like O. oodes, Watson, from which it is 
separated by more conical shape, fewer ribs and different apex. 
ODONTOSTOMIA BIPLICATA, sp. nov. 
(Fig 71.) 
Shell oblong-ovate, imperforate, white. 
Whorls three and an inrolled vertical and half 
buried apex, slightly gradate, separated by a 
channeled suture. Upper whorls angled and 
contracted above the suture. Last whorl 
slightly angled at the periphery. Sculpture— 
last whorl with two small, but sharp revolving 
ridges, one at the periphery and the other 
below the suture, both ascending the earlier 
whorls. Upper whorls otherwise smooth, final 
whorl furrowed spirally by about twenty-five 
fine close grooves beneath the periphery. 
Aperture ovate, acuminate above and below. 
Deep within the throat and confined to the 
posterior moiety, are five strong revolving 
ridges, the remainder of the throat is grooved 
by small revolving striz, answering to the externals culpture. Lip 
sharp, simple, produced anteriorly. Columella with a heavy, 
median, transverse fold, posterior to which is another deeper 
oblique fold. Length 1:46; breadth *7 mm. 
One specimen dredged at 36 fathoms north of Pava Islet. 
Fig. 71. 
This is a well marked species. Not only is it smaller than any 
enumerated in Tryon’s Monograph, but the second, deep seated 
columella fold seems to be unmatched in the genus. The ridges 
in the throat occur in some species from the Red Sea. 
RissOA FINCKHI, sp. nov. 
(Fig. 72.) 
Shell narrow, subulate, turretted, massive, 
small. Colour white with a yellow apex. 
Whorls eight. Sculpture-round the periphery 
of each whorl is wound a heavy tabulate keel. 
The penultimate whorl carries a spiral thread 
above and another below this keel. On the 
last whorl is a raised subsutural thread and 
three basal lyre. Aperture oblique, circular, 
peristome entire, thickened and_ broadly 
reflected. Length 192; breadth ‘92 mm. 
One specimen dredged off Tutaga Islet in 
200 fathoms. 
Named in honour of Mr. A. E. Finckh, 
who made zoological collections on Funafuti Fig. 72. 
