C E R I T II I U M. 



Plate XVI. 



Species 109. (Mus. Cuming.) 



Cerithium albo-liratum. Ceriih. testa, mbintd, co- 

 nica, attci, longitudinaliter plicatd ; anfracliljus paucin, 

 subangulatis, supra minute Uratis, infra prope suturam 

 bicostatis, liris proximis, cost is creiiatis, subdistauti/>us, 

 iutersliiits foveolatis ; aperturd fusiformi, canali bre- 

 viiisculo, valde aperto. 



The wuite-ridged Cerithium. Shell minute, conical, 

 white, longitudinally plaited ; whorls few, rather an- 

 gular, above minutely ridged, beneath, near the su- 

 ture, double-ribbed, ridges close, ribs creuated, rather 

 distant, interstices hollow ; aperture fusiform, cana' 

 rather sliort, very open. 



Carpenter, Mazatlan Report, sp. 336. 



Hub. Mazatlan. 



No mature specimens have yet been found of this inter- 

 esting little species. 



Species 110. 



Cerithium Sayi. Cerith. lestdpurvd, ovali, nigrescevtte ; 

 anfracllbus paucis, subventricosis, loiujiindinitliter pli- 

 catis, spiraliter quadricostatis, costis super pliois tuber- 

 culiferis, suturd excavaid ; ultimo anfractu infra cos- 

 tato ; aperturd siibquadratd, labro interno, exponso, 

 columelld subtortuosd, canali brevissimo, aperto. 



Say's Cerithium. Shell small, oval, nearly black ; 

 whorls few, subventricose, longitudinally plicated, 

 spirally four-ribbed, ribs tuberculated on the plaits, 

 suture hollow ; last whorl ribbed beneath ; aperture 

 rather square, inner lip expanded, columella rather 

 twisted, canal very short, open. 



Menke. 



Cerithium nigrum, Totten. 



Hub. North America. 



A very small, darkly-coloured shell, with four tubercu- 

 lateil ribs ou each whorl. 



distantibus, interstitiis plaiiis ; anfractibus rectiusculis, 

 ad suturam unicostafis ; aperturd subtrigond, columelld 

 brevi, obtusd, labro subincrnssato, canali brevi. 



The changeable Cerithium. Shell small, nearly 

 black, solid, spirally sulcated, longitudinally ribbed, 

 ribs distant, interstices flat ; whorls rather straight, 

 with a rib at the suture ; aperture rather triangular, 

 columella short, obtuse, outer lip rather thickened, 

 canal short. 



C. B. Adams. 



Sab. West Indies. 



Only one variety of this shell appears in Mr. Cuming's 

 collection. 



Species 112. (Fig. a, b, Mus. Cuming.) 



Ceeithium delectum. Cerith. testa parvd, grnciU, mi- 

 nute seriatim gramilata, violaced seu rosed, seu alba 

 minute punctatd, variribns validis, albis ; anfractibus 

 medianis paido inflatis, apice nnmeralo ; aperturd 

 parvd, columelld obtusd, brevi, canali aperto. 



The chosen Cerithium. Shell small, thin, minutely 

 granulated in rows, violet or pink, or white with mi- 

 nute dots, varices thick, white; middle whorls slightly 

 inflated, apex sharp ; aperture small, columella ob- 

 tuse, short, canal open. 



A. Adams. 



ilab. Gallapagos Islands. 



Species 111. (ilus. Cuming.) 



Cerithium mutabile. Cerith. testd pared, nigrescente, 

 solidd, spiraliter sulcata, I'jngitudinuUter costatd, costis 



Species 113. (Mus. Cuming.) 



Cerithium lutosum. Cerith. tesUl brevi, nigrescente, 

 longitudinaliter plicatd ; anfractibus paucis, subventri- 

 cosis, seriebus trihus tuberculorum armatis, inter tu- 

 bercula liris elevatis cinctis ; ultimo anfractu infra 

 alternalim costato et lirato ; aperturd suhquadratd. 

 columelld lata, laminatd, labro intus incrassalo, sub- 

 crenulato, canali obliqiw, brevi. 



The dirty Cerithium. Shell short, rather black, lon- 

 gitudinally plaited; whorls few, rather ventricose, 

 armed with three rows of tubercles, with ridges be- 

 tween the tubercles ; last wliorl alternately ribbed 

 and ridged beneath ; aperture rather square, columella 



December, 1 S65. 



