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P ami 1 J- S erne: 1 i dae . 

 Genus SEI.IELE Schuiaaeher. 

 Section Semele s. s. 



SEfSLE OAlIIGONainnATA n. sp. 



Ijescilption .- Shell small, cubelliptical, r:v^ " •':el;." in- 

 equilateral, raoderacely inflated; roujicTed anteriorl;,- and post- 

 eriorly, the ciijrve of the ajitei^ior enrl more convei^:; antero-dor- 

 sal marc-in straight or L-ili.^htl;; coi.cave, postero-dorsal shorter 

 and slicihtlv conve::; base rentl;; arouate ; umbones lov;, acute, sit- 

 uated behind the median Yertisal; external surfa^^e rcticulately 

 sculptured with strong-, eqiiall;;,' spaced concentric lamellae, their 

 ed°-es thickenect and orenulated at the points of intersection V7ith 

 'orominent radials, the rnr'ials so.iars.ted by s1i":htly v.'ider inter- 

 spaces and closer on the me ;ian portion oi the sr.ell; near the 

 antero- and postero- ventral margins conspicuous nodules developed 

 at the intersections; between the concentric lamellae fine cor,- 

 centric striae present; hii^^e noruial, the right laterals heavy. 



Dinensions .- lerjgth, 9 mm,; alt., 6.5 mm.; semidiam., 

 1.8 mm. 



RenErhs .- The snail, beautifully Dcalptured valves of this 

 species oon not be confused with any other mO'Viber of the fa.U!ia. 

 They closely resemble the young of the Pliocene to Recent 3. 



