﻿R I S S A. 



Plate IX. 



Species 76. (Mus. Sowcrby.) 



RiSSOA CL.WHKATA. J?^-. ( 7?/.s-.s-o;h,() f.'d,! allnJ,^, r!„l,1, 

 solida, cosli's sjiirallhiis fiii,,;i siilnnihi i/iiiiupii' 

 et loiujltn,h-n„i:hi<< /un-j;, ,».,;//,< mnnrrasi, nd 

 angulos nodusls dathmtl^ ; intr,\<fitlis j,n'j)n„i;' 

 foveolatis ; anfractihus altis, conveiimcuUn, uUhmi 

 u7ii'sulcato et varicoso ; aperiurd pyriforiiii, lnhio 

 externa antke prodiido ; colnmelld hrevi, cntsfd. 



The latticed Rissoa. Shell whitish, elevated, solid, 

 latticed with five spiral ribs above the suture, 

 and rather more numerous longitudinal ones, 

 nodose at the angles ; interstices deeply pitted ; 

 whorls elevated, rather convex, the last with a 

 groove and spiral varices behind the columella; 

 aperture pyriform, outer lip anteriorly j)ro- 

 duced, columella short, thick. 



A. Adams. Proc. Zool. Soc. 1851, p. 205. 



Hah. Isl. Bohol, Philippines. 



A beautiful broadly-sculptured species. 



Species 77. (Fig. a, h, c, d, Mas. Brit.) 



EiSSOA variabilis. Bis. testa subfusi/ormi, acinuinald, 

 ienuiter sjiiraliter fiisco, jiunctato-l! tteatd , et sfriatd ; 

 nn/ractibufi octo, edevatis, trihus apicalibus brrihus, 

 alteris medio angulatis, costatis, costis medio ptv- 

 minentibus ; aperfurd dedivi, sitbovatd, manjine 

 expanso, lilaciitd, cxtiis intitaque iiu-rassalii. 



The variable Rissoa. Shell rather fusiform, acumi- 

 nated, finely spirally brown spot-lined and 

 striated ; whorls eight, elevated, three aj)ical 

 smooth, the others angular in the middle ; aper- 

 ture sloped, rather oval, mai'gin expanded, lilac, 

 thickened within and without. 



Mdhlfeldt ? 



Hah. ? 



Species 78. (Mus. Sowerby.) 



Rissoa decussata. Bis. (Bissoiim) testa albd, solidd, 

 altd, tenuissime costellis obliqnis longitiuliiLolibns 

 et spiralibws minuiis demssatd, ap)ict' obtuso ; an- 

 fractihus se,f, infra medium conve.ciitsctdis ; aper- 



turd subpyriformi : cnhunrlhl Ircri, attmuatd, 

 labia externa praiin'iii'tili, (■ra:<sii. 

 The decussated Rissoa. Shell white, solid, high, 

 very finely decussated with oblique longitudinal 

 riblets and spiral stria', apex obtuse ; whorls six, 

 rather convex below the middle ; apertui'e rather 

 pyriform, columella short, attenuated, outer lip 

 prominent, thick. 

 Montagu. Test. Brit. Vol. II. p. 31);>. 

 Hah. West Indies. 



A West Indian shell described as British by Mon- 

 tagu. It has a smooth, and even a polished appeai'ance 

 until examined with the lens, wlien the oblique longi- 

 tudinal ribs and fine spiral strias are seen. 



Species 70. (Mus. Sowerby.) 



Rissoa sim.exdida. Bis. tesld hre.viter subfn.^ijunni, 

 fidrd, :<j,iralilrr lin< is rnbris pimctatis picfa ; 

 spiri! anniiiiiatfi ; anfroctihus sex, hrcribnn, 

 cuKjnlatiin coslatis, inter et infra cuslas fi^co 

 fasciatis ; aperiurd bnri, labio externa infii.f 

 extiisquo crasso violaceo miin/inatu. 



The splendid Rissoa. Shell shortly subfusiform, 

 fulvous, spirally painted with red punctured 

 lines, spire acuminated ; whorls six, shoi-t, 

 angularly ribbed, banded with brown between 

 and under the ribs; aperture short, outer lip 

 thickened within and without, edged with violet. 



ElCHlO — • — ? 



Hal. Black Sea. 



Shorterand more finely ribbed than Bissau variidiilia. 



Species 80. (Mus. Sowerby.) 



Rissoa Sagealana. Bis. {Bissnina) testa alhd, sulidd, 

 alia, piiramidatd ; anfrartihn^ sri'lnn, i-osli^ rre- 

 nalis, ahliquis, transuersi lirafix. srnlj:!!^ ■ a i,, rtiira 

 piiriformi, labio externa erasxin^inm, a ntic'- [o-cdnrla. 



The Sagra Rissoa. Shell white, solid, high, pyra- 

 midal ; whorls seven, sculptured with oblique 

 crenated ribs ridged across ; aperture pyriform, 

 outer lip very thick, anteriorly produced. 



D'Orbigxt. Mollusques de Cuba. 



Hab. Cuba. 



