148 MOLLUSCA. 
CERITHIUM IRRORATUM (Gould). 
Testa ovato-conica, transversim striolata, fusco-nigricans, punctis elon- 
gatis cinereis trrorata: spira conica, anfractibus septem planulatis, 
longitudinaliter undulatis, ultimo dimidiam teste superante ; sutura 
obsoleta: apertura rotundato-elliptica ; labro dechivt ; canal brevissimo; 
Sauce livida, albo-fasciata. 
Cerithium irroratum, GouLtp; Proceed. Boston Soc. Nat. Hist., 11. 
119. May 1849. Expedition Shells, 61. 
SHELL of medium size, rather solid, short ovate-conic, surrounded 
by numerous fine strie; colour dusky, sprinkled with numerous 
minute, elongated, whitish dots, arranged in the interstices of the 
strie. Spire short, conical, composed of seven or eight whorls, on 
which are about eight oblique undulations, and so continuous 
that the suture is barely perceptible: the last whorl is more than 
half the length of the shell, rounded at base. Aperture rounded 
oval, nearly destitute of a posterior canal, and with a mere basal 
notch in place of a rostrum; columella arcuated, whitish, with a pos- 
terior callus. 
Length three-fourths of an inch; breadth four-fifths of an inch. 
Generally resembling C. ocellatum, Lam., which has a median 
tuberculated angle on each whorl, and an excavated sutural region, 
while this has a regularly curved outline and folded surface. The 
pale spots are less numerous, and the proportions of the aperture are 
different. 
Figures 168, 168 a, two views of the shell. 
CERITHIUM CHLATUM (Couthouy). 
Testa subulato-turrita, dilute rufa: spira anfractibus ad tredecim via 
convexis, longitudinaliter crebré sulcatis, et liners duabus impressis 
cinctis, ultimo anfractu ad basim inornato; suturad impressa: aper- 
tura rotundata ; columella arcuata, rostro brevissimo. 
