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Subfaiiily Tindarinae. 

 Genva TlWDAIilA Bellardi. 



TIITDARIA OAILIPIGTA n. sp. 



Descript ion .- Shell small, polished, veneriform, trans- 

 versely subovate, raodLratelj" inequilateral, well inflated; round- 

 ed anteriorly and posteriorly, the anterior dorsal margin slight- 

 ly helovy the level of the posterior and rounding more eonvexly 

 into the symmetrically arouate base; umbo tumid, relatively nromi- 

 nent, prosogyrate, situated before the median horizontal; external 

 surface sculptured with regular relatively coarse concentric rugae, 

 obsolete on the umbo and near the dorsal m.ar?-ins; ligament exter- 

 nal, opisthodetic, the area very narrow and shallow, obscurely 

 truncating the proxi al portion of the posterior series of teeth; 

 chondrophore absent; teeth in two scries, separated by a short, 

 transversely elongated, subumbonal lamella; the conve- posterior 

 series numbering fifteen teeth, reduced in size toward the umbo 

 and the dorsal portions of the seven proximal teeth obscured by 

 the iTimersion of the ligam.ent ; anterior series slis-htly concave, in- 

 cluding seven teeth, the distal five heavy and the proximal two 

 abruptly reduced in size; interior of the shell polished; ant- 

 erior muscle scar placed under the distal extrerr.ity of the hinge; 

 relatively large; posterior scar and pallial line obscure. 



