CERITHIDEA. 



Plate II. 



Species 9. (Fig. a, b, Mus. Cuming.) 



Cehithidea ambigua. Cer. testa pyramidaU, acumina- 

 ta, fused, costls subiwdosis arcuatis longitudinaLibus 

 oritatd ; aiifractibus numerosis, rotimdis, suturd pro- 

 funda, uUiino anfrnctu infra cariuato ; aperturd parvd, 

 columella laminatd, labro subexpamo, infra produclo. 



The ambiguous Cehithidea. Shell pyramidal, acu- 

 minated, brown, with slightly nodose, arched, longi- 

 tudinal ribs ; whorls numerous, round, suture deep, 

 last whorl keeled beneath ; aperture small, columella 

 laminar, outer lip somewhat expanded, produced be- 

 neath. 



C. B. Adams, 'Shells of Jamaica.' 



Ilab. Jamaica. 



DifFerins; from C. costata in the ribs beins; nodulose. 



Species 10. (Mus. Cuming.) 



Cerituidea costata. Cer. tedd pi/ruinidali, acumina- 

 ta, nigrescente, costis Icevibus arcuatis longitudinalibus 

 ornatd ; anfructibns numerosis, rotundis, suturd pro- 

 funda, ultimo anfractu infra unicariuato ; aperturd 

 parvd, columella laminatd, labro siibexpanso, infra 

 produclo. 



The ribbed Cerithidea. Shell pyramidal, acuminate, 

 rather black, ornamented with smooth, arched, longi- 

 tudinal ribs; whorls numerous, round, suture deep, 

 last whorl keeled beneath ; aperture small, columella 

 laminar, outer lip somewhat expanded, produced be- 

 neath. 



Wood, Ind. Test. Strombus, sp. -13. 



Ilab. Jamaica. 



The ribs in this species are plain, and not nodose, as in 

 C. ambigua. 



Species 11. (Fig. a, b, Mus. Cuming.) 



Cerithidea Rissoidea. Cer. testa pgramidali, fused, 

 costis subcaruleis longitudinalibus obliquis, eleganter 

 arcuatis, infra noduliferis, ornatd; anfraclibus convcris, 

 infra spiral iter costatis, suturd prof undd ; aperturd ro- 



tunda, fasciatd,columelld arcuald,labro cr.isso, expunso, 

 ad basin produclo, canali inconspicuo . 



The RissoA-sHAPED Cerithidea. Shell pyramidal, 

 brown, ornamented with bluish, longitudinal, ele- 

 gantly-cm'ved, oblicpie ribs, which are noduliferous 

 beneath ; whorls convex, spirally ribbed beneath, 

 suture deep ; aperture rounded, banded, columella 

 arched, outer lip thick, expanded, produced at the 

 base, canal not conspicuous. 



Sowerby, Thesaurus, f. 289. 



Cerithiuin crassilabruni, Krauss. 



Hab. Port Natal. 



The light-blue ribs are elegantly curved and regular. 



Species 13. (Fig. a, Mus. Sowerby; Fig. i, Mus. Cumiug.) 



CERirillDEA CllARBONNIKRi. Cer. testa tenui, corned, 

 J'uscd, pi/ramidali, Iceoi, longitudiunliter costata, costk 

 lavibus, stibdislantibus ; aufractibus subplunatis, ulti- 

 mo angulato-carinato , infra spiraliler striato; aperturd 

 subquadratd, infra emarginatd, columelld brevl tenui, 

 labro expanse, rejtexo, infra produclo. 



Charbonnier's Cerithidea. Shell thin, horny, brown, 

 pyramidal, smooth, longitudinally ribbed, ribs suiooth, 

 rather distant ; whorls ratiier flat, the last angulated, 

 carinated, spirally striated beneath; aperture nearly 

 square, emarginated beneath, columella short, thin, 

 outer lip expanded, reflected, produced beneath. 



Petit, Journ. Conch. 1851. 



Cerithium unicarinatuui, Metcalfe. 



Hab. Borneo. 



A very distinct, light, horny species, with carinated 

 whorls and square mouth. 



Species 13. (Fig. a, b, Mus. Cuming.) 



Cerithidea rhizoperarum. Cer. testa ci/lindricd, so- 

 lidiiisculd, costis tuberculatis longitudinalibus, paulo 

 arcuatis el liris spiralibus cancellutd ; anfractibus uni- 

 fasciatis, brecibus, ultimo angulato, subcarinato ; aper- 

 turd rolnndd, ad basin columella' valid'e emarginatd, 

 labro e.rpanso, infra producto. 



March, 1866. 



