124 Zoological Society. 



balonga, island of Saraar ; in ten to thirty fathoms, mud : Sorsogon, 

 island of Luzon : — all in the Philippines. 



Cab. Cuming. 



These little shells resemble each otlter very closely, and it is only 

 by close attention to minute characters and the proportion and 

 form of the last whorl that they can be satisfactorily discriminated. 

 The present species is perfectly smooth, and the last whorl is large, 

 of a squarish form, and full and rounded. The upper portion of the 

 aperture is strongly denticulated. 



RiNGicuLA PROPiNQUANs. Rin. testd ovatd, retusd, striatd, nitidd ; 

 anfractibus rotimdatis, ultimo magna valde rotundato, concinn>- 

 striato. Axis 1^ lin. 



Hab. Sual, Philippines; in five to seven fathoms, sandy mud. 



Cab. Cuming. 



Here the last whorl is not so square in shaj)e, but very full and 

 rounded, and is neatly striated in a veiy regular manner, and the 

 spire is short. Till the light is thrown properly on them, these striae 

 are not very evident, but once discovered they will be found con- 

 stant. 



RiNGicuLA CARox. R'ui. tcstd ovatd, acuminatd, striatd, nitidd; 

 anfractibus rotimdatis, ultimo subtransverso, rotundato, distanter 

 sti'iato ; spird exsertd ; aperturd subabbreviatd ; labro cor rug at o. 

 Axis 1^ lin. 

 Hab. Straits of Malacca; in seventeen fathoms, mud. 

 Cab. Belcher. 



The greatest breadth of the last whorl is probably in the transverse 

 direction, and it is grooved with striae placed at regular distances 

 from each other. The spire also is proportionately lengthened. 



RiNGicuLA EXSERT.\. Rin. testd ovatd, acuminata, l<Evigatd,politd ; 

 anfractibus rotundatis, lavigatis ; spird elongatd ; labro pone valde 

 incrassato. Axis 1^ lin. 

 Hab. Camiguing ; in forty fathoms, sandy mud : Sorsogon, island 

 of Luzon ; in six fathoms, coarse sand ; — both in the Philippines. 

 Cab. Cuming. 



Compared with R. grandinosa, the last whorl is small, but agrees 

 in being quite smooth and round ; the spire is elongated, as in i2. 

 caron, and the labrum is even rather more reflected than is usual. 



RiNGicuLA AUSTRALis. Rin. tcstd ovatd, acuminatd, Icevigatd, po- 

 litd ; anfractibus rotundatis, penultimo sensim minors ; spird elon- 

 gatd, infra suturam fascid subalbidd cinctd. Axis 1^ lin. 



Hab, Port Lincoln, Australia. 



Cab. Metcalfe. 



The only specimen before me has not attained its full adult age. 

 In its characters it is rather intermediate ; the spire is not so promi- 

 nently produced, and the penultimate whori is more than usually 

 developed, so as to be more intermediate in size between the others. 

 All these species are of one uniform glassy semiopake colour, in 

 some individuals being more glassy, in others more opake. 



