POTAMIDES. 133 



NOTE IX. 

 A NEW POTAMIDES 



BY 



M. M. SCHEPMAN. 



Potamides (Terebralia) tenerrimus n. sp. 

 (Plate 6). 



Shell pyramidal , slightly decollated , thiu , fragile , mo- 

 derately shining, blackish-brown, remaining whorls ö'/g , 

 inflated , with a deep suture ; sculpture consisting of flat ridges 

 separated by superficial grooves. Of these ridges there are 

 5 or 6 on the upper whorls and about 17 on the last 

 whorl , where they reach to the base ; the ridges are crossed 

 by more or less distinct lines of growth, which produce 

 here and there small granules, especially towards the 

 upper part of the whorls ; last whorl with a varix opposite 

 to the margin of the aperture or slightly backwards. 



Aperture ovate , outer margin expanded , thickened in- 

 ternally, sinuous and ascending above, produced in the 

 middle , ending in an obtuse angle below ; columella with 

 a thin smooth callus , with an obtuse angle or fold below ; 

 canal extremely short, enclosing a rather deep sinus. 



Operculum thin, light horn-colour, with an impressed 

 central nucleus, surrounded by several laminae. 



The measurements of the largest specimen are: 



Alt. 19, diam. inch perist. 11 mill.; Apert, alt., 8, lat. 

 6 mill. 



var. costata mihi shell more elongate with numerous ribs. 



Alt. 19, diam. inch perist. 9'/2 mill. 



Notes from thie Leycleii Museum , "Vol. XVI. 



10 



