96 Mr. J. C. Melvlll on the 



Brusina, from the Mediterranean, P. monocycla, A. Ad., 

 from Japan, and P. callista, Melv., from the Indian Ocean. 

 Verj recently (1898) Prof. Ralph Tate has described 

 P. MayW^ from Tasmania, which by the figure must be close 

 tOj if not actually identical with, P. calUsta. 



Lacuna tenuistnatUj sp. n. (PI. II. fio-. 5.) 



L. testa ovato-orbiculari, pallide straminea, versus apicem puuieeo- 

 sufFusa, tenui, anguste umbilicata ; anfractibus quatuor, apicali 

 incluso subpapillari, Isevi, tumidulis, apud suturas impressis, 

 arctissime spiraliter tenuistriatis, ultimo rapide accrescente, efFuso ; 

 apertura hmari, labro exteriors tenui, paullum efFuso ; margins 

 columellari apud basim crassiusculo, nitido, albo, apud umbilicum 

 canaliculato. 



Long. 15, lat. 10 mm. 



Bah. Muscat, Persian Gulf, at 7 fathoms. 



A most interesting addition to the genus, from the known 

 species of which it differs in greater tenuity, ovate-orbicular 

 form, flattened apex, lowest whorl roundly effuse, the whole 

 surface being most closely and finely spirally striate. Mouth 

 lunar; outer lip thin; columella slightly thickened towards 

 the base, white, shining, canaliculately grooved in the region 

 of the narrow umbilicus. L. itidtca, E. A. Smith, is the only 

 other true Lacuna hitherto recorded from tropical seas. 



Priotrochus sepulchralis, sp. n. (PI. II. fig. 6.) 



P. testa scmiglobosa, anguste umbihcala, gradatula, solida, alba, 

 ochraceo-stramiuea vel, rare, puuiceo-variegata ; anfractibua 

 quinquc, apicali acuminato, la)vi, cseteris gradatis, spiraliter filo- 

 costatis, costulis acutis, ultimo et penultimo infra suturas spiraliter 

 ano-ulatim coronatis ; apertura obliqua, rotunda, iutus arete 

 sulcata; labro exteriore efFuso, crassiusculo; margine columellari 

 incrassato, albo, nitente. 



Alt. 11, lat. 10, diam. 10 mm. 



Hab. Kais Island, 9 fathoms, coral-sand. 



Several examples, some subfossil. Semiglobular in form, 

 with turreted whorls, the last two possessing, just below the 

 sutures, a spiral coronation of nodules ; the apical whorl is 

 smooth, the remainder being spirally acutely costulate to the 

 base of the last whorl. The aperture is obliquely rounded, 

 within sulcate ; outer lip thick, somewhat effuse ; columclhir 

 margin thickened, especially in the proximity of the narrow 

 umbilicus. 



* Trans. Roy. Soc. S. Australia, 1898, p. 84, pi. iv. fig. 6. 



