nOTELLA. 1 37 



siituram monilifera ; ad angulum alba, infra interruptiin 

 fasciata ; callo tenui ; columella mediocri. — A lighter sliell 

 than R. costata, with slighter grooves and thinner callus 

 and columella. The upper part of the last whorl and a band 

 on the lower are grey, prettily marked ; the sutural margin is 

 beaded, and tlie apex whorls fawn-coloured. 



10. TRiLOBATA, f. 14, Sowevby. — Solida, leuticularis, griseo- 

 fulva, maculis strigisque varie picta ; callo umbilicali parvo, 

 ad columellam juncto ; columella trilobata. — The umbilical 

 callus seems to form a part of the columella, making it, with 

 the upper and lower parts, a three-lobed column. 



11. STRiOLATA, f. 18, A. Adams. — Spiraliter striata, R. 

 trilobatce similis sed superne magis conica, angulo anfractu 

 ultimi carinato; callo umbilicali parvo, ad medium columellye 

 juncto; columella superne infraque tenui. — More angular 

 than the preceding, and although the callus is confluent with 

 the columella in the same way, there are not lobes above and 

 below. 



12. GUAMENSis, f. 28, 29, Quoy. — Ventricosa tenuiuscula 

 depresso-rotundata pallida, fulvo rubroque varie maculata 

 et flammata ; anfractu ultimo magno, rotundo ; spira parva ; 

 callo umbilicali roseo, moderate expanso. — The most rounded 

 and ventricose of the species, with a moderately broad um- 

 bilical callus. 



13. SAGITTATA, f. 9, Hinds. — Subdepressa, superne conica, 

 fulva, maculis nigrescentibus sagittatis seriatim ornata ; 

 ultimo anfractu rotundato ; callo parvo, circumscripto. — 

 Resembling R. guamensis in form, with arrow-headed mark- 

 ings, rounded last whorl, and small circumscribed callus. 



14. PERSPicuA, f. 17, A. Adams. — Minuta alba compressa 

 lenticulari, apertura transverse ovata, callo ventrali semi- 

 lunari. — The writer has not had a recent opportunity of exami- 

 ning this shell, and regrets that the figure has not come out 

 well in the lithographic plate. It is not certain that it really 

 belongs to the genus. 



