188 



TJXIONIDjE. 



Aery gently arched ; ventral margin scarcely rounded in the 

 anterior and median regions, slightly curved posteriorly ; anterior 

 side abruptly rounded; posterior side sloping above, then angled 

 and very abruptly descending ; cardinal tooth in left valve 

 obtusely triangular, erect ; absent in right valve ; lateral teeth 

 anteriorly short, deeply grooved and projecting in right valve, 

 erect and jagged in the left, posteriorly moderately elongate and 



Pig. 21.— 1 & 2. LameUidem (i.) naminforcnm, Pres-ton. (Type.) Nat. size. 

 3. Hinge and nuisciilar scars of same. 



bifurcated in both valves ; anterior scars rather circular, deep ; 

 posterior scars lightly impressed ; interior of shell pale flesh- 

 colour, shading to iridescent bluish -white, A'ery minutely 

 granulate. 



Long. 35, lat. 8 J: mm. 



Hob. Narainpore Bhil, Murshedabad District {Major C. J. 

 Itobertso7i-Milne, IM.S.). 



The type specimen is in the Indian Museum. 



