APPENDIX MOLLUSCA. 



557 



Fig. 71. 



This species is most like 0. 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 striae, 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. 



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. 



RlSSOA FINCKHI, 8p. HOV. 



(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 lyrae. Aperture oblique, circular, 

 peristome entire, thickened and broadly 

 reflected. Length 1 92; 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. 



