﻿RISSOA. 



Pl.ATK X. 



:hl.'ii'ii\ aperturd uhliqiw 

 ,,r,nr,,so: eolumcUd oh- 



Species 86. (IMus. Crosse.) 

 Risso.\ (uemistomia) Caledonica. 7i*/,-;. tesfd dlbidd,, 

 hEvlijatd, ohlonijo.i'caJd, Ifimi, apicc obtusu ; an- 

 fradibus quinqiic, 

 ssemilunari, labw > 

 h'qud, iiifrd acuminatd. 



The CALEnONlAN RiSSOA. Shell whitisll, Slllnotll, 



oblonjr-ovate, thin, with obtasc apex; whorls 

 five, the last oblong, aperture obliquely semi- 

 Innar, outer lip expanded ; columella oblique, 

 acuminated below. 



Crosse. Jonrn. Conch. Vol. XII. p. 72, 1872. 



Hub. Noumea, New Caledonia. 



This sliell bears so strongly the aspect of a true 



typical Risfoa that, in the absence of an operculum, 



it seems dillicult to understand why a new genus 



should be created for it. 



svperioribus jjnri'w, attenuaUs, apice acuniiiiafo, 

 apvrturd subtriijond, labia externa prodac.lo, rn't:- 

 siusciilo: columelld supenie iucmsxatd, iiifrd .s-h./.- 

 tniHi-ald. 



The uih-striated Rissua. Shell pyramidal, white, 

 thin, arched, finely ribbed, spirally striated, 

 last and previous whorls a little inflated, upper 

 small, attenuated, ajie.ic acuminated ; aperture 

 sulilrigoiial, culrr lip pnulueed, rather tliick ; 

 coluiuella thickenril aliove, slightly trmieatv 

 below. 



D'Oruiont. Voy. Amer. !Meridionale, p. 31t-i>. 



llab. St. Vincent's, West Indies. 



Species 87. (Mus. Brit.) 



Rissoa (oiNA) STElCTA. Bis. testd solidd, pupceforiiii, 

 pallide fulvd, altd, redd ; anfradibus odo ; api- 

 calibus attenuatis, aciimtnatia ; mediants subiii- 

 JJatis, redilateralihiis !<it/i,'ni,'- jifrj[iriidicitJiirili'r 

 custatis, ultimo infra hiri^jatn; aprrtnrd p'trn!, 

 semilunari, eolumtU :i hnvi, obliqiui, infra tntni-iild, 

 labio externa expanso, actito. 



The straiijutened Rissoa. Shell solid, pupa-shaped, 

 pale fulvous, raised, straight ; whorls eight ; 

 apical attenuated, acuminated, middle somewhat 

 inflated, straight-sided, perpendicularly ribbed 

 on the upper side, the last smooth below ; aper- 

 ture small, semilunar, columella short, oblique, 

 truncated below, outer lip e.'i])anded, sharp. 



Menke. Zeitschrift fiir .Malak. IX-V). 



Hub. Cape St. Lucas. 



Rissoa fortis is a more broadly-ribbed, darkly- 



colom-ed shell. 



Species 88. (Mus. Brit.) 

 Rissoa (oina) striaticostata. Eis. testd, pymmidatd, 

 albd, teiiui, arcuatd, tenuiter cu.^tntii, sjiiraliter 

 striata, anfractibus ultimo et penidtinw stibiujlatis, 



Species 8'.». (Mus. Brit.) 

 Rissoa (oina) Chesseli-u. A'/x. ti:-<td albd, stib/'jird. 



midatd, solidd, COi-tis salidi.-- obliqnr jlrj;„,sis , / 

 striis spirnlibus, elevatis, caiicll.ild ; spird <u->n„i. 

 iiiild, infriirlibus apicalibus al'rn itutis. iilliiin: 

 iiifrnclii. iiijlito; aprrturd jiarrd, xiijin) infriiqiir 

 subcavalirnlntd, Iiibiu i.rlrn,,, crass,,, creuulata. 



Chesnell's Risspa. Shi'll wiiite, rather pyramidal, 

 solid, cancellated with (ilili([uely flexuous solid 

 ribs and spiral striie ; spire acuminated, apical 

 whorls attenuated, last whorl inflated ; aperture 

 small, slightly channelled above and below; outer 

 lip thick, crenulated. 



Michaud. Cat. Ris. p. 17, f. 23-24. 



Sab. India. 



Species 90. (Mus. Brit.) 

 Rissoa (oina) Buueana. Ills, tcstd pallida, sa'.idd, 



obtuse pljratnidatd, tari.jatd, Irnnisslnn: riircicas- 

 tatd ; apertard parvd, snhl ri,jn,id, ,-nhi luclla rrassd., 

 brevi, subtorttid, subtrtuicatd, labia r.rt.-rua rrasso. 

 The Burean Rissoa. Shell pale, solid, obtusely 

 p^-ramidal, smooth, very slightly bent-ribbed ; 

 apertui-e small, subtrigonal, columella thick, 

 short, rather tortuous, almost truncated, outer 

 lip thick. 



SOVVEEBT. 



R. cuncinna. Adams. 



Hab. Isl. Bnrea, Philippines. 



