﻿RISSOA.— Plate XL 



Brown's Rissoa. Shell small, pyramidal, acuminated, 

 fulvous, smooth ; whorls six, rather elevated, 

 the last somewhat round; aperture pyriform, 

 outer lip obliquely produced. 



D'Orbigny. Voyage dans I'Amerique ]Meridionale. 



]Tah. St. Vincent's. 



Species 102. (Mus. Brit.) 



BissoA (oina) TKiTiCEA. Bis. testo, hrevi, crassd, alba, 

 pupoifonid ; anfraetibiis hrevilus, costatis ; cost is 

 aruuatis, Icevihus, rotundis, infra medium anfradus 

 nltimi desiiientibus ; ultimo anfradu brevi ; ai'er- 

 turd parvd, subauriformi, antice rotundatd; lahio 

 erasso, rotunda ; uolumelld brevi, continuo. 



The wheat Rissoa. Shell short, thick, white, pupa- 

 shaped ; whorls short, ribbed, ribs curved, 

 smooth, round, ending below the middle of the 

 last whorl, last whorl short; aperture small, 

 rather auriform, anteriorly rounded, lip thick, 

 rounded, columella short, continuous. 



Pease. Proc. Zool. Soc. 1860, p. 438. 



Hii/i. Pacific Ocean. 



Ri 



Species 103. (Mus. Brit.) 



SOA (oina) Philii'PIANI. His. ijstd tiirrit<i, pallidi- 

 fulr 



t^rditi 



luinjltiuliiialiter crdm cnstat, 

 riiifrllntix : aiifrdctibus senis, redis int siiliiniiii 

 lUKjidiifls ; ultimo avfradu ivfrd sjiiralitcf rudatd, 

 aperturd parrd, subuvatd, columella lata, subar- 

 cnatd. 



PHiLirn Rissoa. Shell turreted, pale fulvous, 

 longitudinally closely ribbed, interstices cancel- 

 lated ; whorls si.TC, straight, with an angle at the 

 suture, last whorl spirally grooved on the under 

 side ; aperture small, subovate ; columella broad, 

 a little curved. 



PfElFKER. ? MS. Brit. Mus. 



Rissoa cancellata. Philippi. 

 Hah. Cuba, Jamaica. 



Species 10-4. (Mus. Brit.) 



Rissoa (oina) Woodwaedi. His. testd minutd, hreviter 

 pyrainidatd, pallidissime fulvd ; anfradibus senis, 

 brevibus, longitudiiialiter costatis; costis oblique 

 arcuatis, lmvib^ls, rotwudis ; ultimo anfradu iiifra 

 unicostaio ; aperturd parvd, jyyriformi ; labia ex- 

 terna crasso, anfradu apicali rotunda. 



Woodward's Rissoa. Shell minute, shortly pyra- 

 midal, very pale fulvous ; whorls six, short, 

 longitudinally ribbed, ribs obliquely arched, 

 smooth, rounded, last whorl single-ribbed below: 

 aperture small, pyriform ; outer lip thick, apical 

 whorl rounded. 



Carpenter. Shells of Mazatlan, p. 357. 



Eissoa clandedinn. C. B. Adams. 



Kissoafirmata. C. B. Adams. 



Eab. Mazatlan. 



Species 105. (Mus. Brit.) 



Rissoa (oina) trochlearis. Bis. testd breviusculd, 

 crassd, rubra fused, spiraliter co.itis angulatis 

 cindd ; anfradibus senis, brevibus, medianis paidii 

 iiijiittis ; aperturd alba, subovatd ; columdln 

 crassd, brevi ; canali conspicuo, labia erterno intiis 

 incrassata, extus crenato. 



The coil Rissoa. Shell rather short, thick, red- 

 brown, spirally belted with angular ribs ; whorls 

 six, short, middle ones a. little inflated ; aperture 

 white, subovate ; columella thick, short ; canal 

 conspicuous, outer lip thickened within, crenated 

 without. 



Carpenter. MS. Smithsonian Inst, and B. M. 



Bissau sulcifera var. Gould. 



Bissoa ligata. Gould. 



Bissoa anmdaia. Dunbar. 



Hah. ? 



