- 51 \ - 



ABRA DEUTEHA n. sp» 



Deserj-Qtion .- Shell sr^.all, thin, • - ell-infls, ted, siibtric-on- 

 al, sub equilateral, iDoin,? slightly/ more ororiaced anteriorly; 



dorsal raarcrins virtually; straij^ht, the anterior sll'-rhtlsr lonsrer; 

 rour.ded anteriorly a::d noE-^c-riorl;; with a very slip-ht constrict- 

 ion near the posterior end; Dace o.eciderLly arcuate; umlDO tumid, 

 low, subceiitral in position; external surface sculptured with 

 very line, refrularly soaced concentric striae, occasion-ally en- 

 phasized into snari^, thin lar..]. " , and fine, r.iore ooscure, 

 widely STScerl radial nErkinc-s ; right volve v.-ith a narrov/ resiliary- 

 .groove, the cardinals ai- laterals, relatively stron?. 



DiEiensions .- Lat., 4 ..v::i. ; ali;., ; .5 ra:.; semiuiara. , 1.6 nim. 



i^eimr :s .- A. deiitera is known from two ri^rht valves. It 

 is distinguished from the yo.ing of A. triarfulata by its ler-s acute 

 umbo, greater inflation and the presence of v/ell-def incd s.?xilp- 

 ture. V/hen the shell is translucent the radials are very ob- 

 scure. 



Occurrence.- lower lliooene : -^a';den be Is, Bov.'den, Jamaica. 



