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13. Nerrra inrerrupra. N. testd ovato-semiglobosd, apice valde 
corrosd et truncatd, olivaced, lineolis luteis interdum interruptis 
creberrimis et fascits latiusculis luteis transversis pictd ; aperturd 
extis semi-ovali, intits luted ; labio subsemilunari, plano-concavo, 
margine in medio arcuato, acuto, dente cardinali exserto. 
Lat. 0°96 ; conv. 0°64 poll. 
Hab. Yba, province of Zambales, isle of Lucon: on stones in a 
rapid river. 
The flat and greatly eroded summit does not allow the form and 
length of the shell to be ascertained with exactitude. It appears to 
me to have at most a whorl and a half faintly depressed below the 
suture. 
Operculum very like that of N. bicolor, but of a yellowish white 
colour externally. On the inferior surface I observe that the upper 
tooth is stronger; the lower one annulated transversely, in a more 
distinct manner. The intermediary plate is more compressed and 
less sinuous at the margin, and the notch at the posterior part ap- 
pears to me to be deeper. 
14. Nerira ancutosa. N. testd ventricoso-globosd, superné de- 
presso-pland, subtis angulosd, olivaced, maculis luteis parvulis ob- 
soletis notatd; anfractibus duobus inequaliter rugatis ; supremo 
deroso-concavo, aperturd subrotundatd, antice et postice angustatd, 
superne et inferne dilatatd ; columelld angustd, medio concavd, su- 
perne callosd, antice tenu® denticulatd, medio emarginatd. 
Long. 0°72; lat. 0°92 ; conv. 0°60 poll. 
Hab. Casan, province of Misamis, island of Mindanao: on stones 
in a small stream. 
Operculum oval, waved with grey on the anterior side, with a 
narrow circular furrow ending in a strong posterior notch: this fur- 
row bounds a superior, obtuse and circular angle. The summit of 
an orange colour; internal surface bearing a curved rib in the centre, 
of greater or less width. Superior tooth yellowish and obtuse; the 
inferior yellowish white and substriated lengthwise ; the intermediary 
plate between the two teeth of a citron colour, cut obliquely at the 
margin. ‘The depression existing at the base of the lower tooth is 
of a flesh-colour approaching to cinnamon. 
15. Nerira crrcumvo.uta. N. testd globoso-subovatd, dilute fulva 
in roseo vertente, punctis luteolis anticé lineis nigris marginatis 
marmoratd, zonis nigris remotis circumcinetd ; anfractibus duobus 
nigro-marginatis ; supremo obtuso, decorticato; aperturd albida ; 
labio plano, superne calloso, antice ruguloso, et in medio arcuatim 
emarginato. 
Long. 0°72 ; lat. 0°84 ; conv. 0°68 poll. 
Hab. ad Insulas Philippinas. 
Operculum of a Clithon, oval, of a rosy white, with a broad, rather 
concave and central furrow; on the interior face of a pale yellowish 
colour, shaded with rose. One lamellated and pointed tooth near 
the summit, and an inferior one, which is circular, subcanaliculated 
in the centre, and striated transversely. 
