398 Mr. Cosmo Melvill on the 



apertura intus striata^ labro simplici^ columelld obscur^ 

 triplicatd. 



sp. maximae. sp. minimae. 



Long. 38 m. 28 m. 



Lat. 18 „ 12 „ 



Hab. Mauritius. Aden. 



Of uniform tawny ochreous colour, paler at the points 

 where the ribs are crossed at the angle of the whorls by the 

 transverse riblets. It varies a good deal in size, and the 

 five specimens I have, embrace all the differences between 

 the extreme measurements here given. It seems to belong 

 to the same group as the last species described. 



I have had six specimens of this till now undescribed 

 shell for many years, obtained at the sale of the collection 

 of Mr. W. J. Hamilton, in March, 1870. One of these 

 specimens, the type figured, is now in the National 

 Collection, South Kensington. I have unusual pleasure in 

 associating with this species the name of Edgar A. Smith 

 Esq., F.Z.S., Curator of the Molluscan Department, British 

 Museum, who has given me much valuable and valued 

 assistance in the preparation of this historical account of 

 Latirus and Peristernia. 



8. Peristernia retiaria, sp. nov. (Fig. 13.). 



. P. testd fusiformiy pallide flavo-ochraced, crassiusculd^ 

 anfractibus septem^ rotundatis^ subventricosis^ longitudinaliter 

 costatis^ costis subangulatis^ indistinct^ fulvopunctatis^ costulis 

 transversim cingulatis^ labro tenuis aperturd oblongd^ basi 

 nigro-ccsruled. 



Long. 20 m. 



Lat. 8 „ 



Hah. Mauritius. 



A delicate looking, though non-transparent shell, and of 

 rather thicker substance than one would imagine, of a pale 

 cchraceous colour, with indigo blue base, the ribs are very 



