from the Province of Tavoy. 457 



In size and exterior, it closely resembles S. aherratn, Sou- 

 leyet, but is rather larger. The aperture of the latter is, 

 however, smaller, and ringent with teeth, besides having three 

 folds near its channelled umbilicus. Its aperture is more 

 nearly like S. Souleyetiana Petit ; but the latter is described 

 as having its umbihcus extending into a canal, and its peris- 

 tome sub-continuous. 



I dedicate it to ^I. Petit de la Saussaye, one of the most 

 accomplished conchologists of the present day, who has added 

 several species to this subgenus, and to whom I am under 

 many obligations. 



BULDIUS ATRICALLOSUS. 



Plate XXIV. Fig. 3. 



Testa solida, imperforata, oblongo-ovata. vix striata, sulpiiurea ; anfr. 7 convex- 

 iusculis, ad suturam constrictis ; apertura lunato-ovali, basi sub-effusa, labro albo, 

 reflexo, marginibus callo atro juactis. 



Description. 



Shell imperforate, elongated ovate, solid, smooth, and 

 shining, of a sulphur-yellow color ; w'horls seven, moderately 

 convex, somewhat girt in near the suture ; last whorl nearly 

 two thirds the length of the shell ; aperture ovate-lunate, 

 somewhat angular at base, and slightly effuse ; lip white, 

 widely revolute, not flattened ; columella white, the callus 

 uniting the extremities of the peristome, and, as far within 

 the shell as can be seen, pitchy-black ; from the midst of it, 

 extending across the penult whorl, is a line of tlie same color, 

 showing the termination of a former stage of growth. 



Length 2^ inches ; breadth 1 inch. 



Two specimens of this shell were received. They are of 

 the same type as some of the shells from the Philippine 

 Islands, as vittntus, Dryns, and mncuUfcrus. The black or 

 molasses-colored callus seems to be constant, and distributed 

 as in B. iostoma ; though I have a shell, probably from Singa- 

 pore, which is somewhat sliorter, more ventricose, and with 

 one whorl less, and the entire aperture while. 



51 



