Wolf and twins series.     AE Semis, c. 169-158 BC.   Obv.    Laureate head of Saturn right; behind, S.        Rev.   Prow right; above, wolf and twins; before, S; below, ROMA.     Cr. 183/2.     13.88 g.   25 mm.      RRR.  Extremely rare, seldom offered. Dark patina with minor earthy deposits. Scratches on obverse.    VF.