Butterfly (and vine branch) series. AE As, c. 169-158 BC. Obv. Laureate head of Janus; above, mark of value I. Rev. Prow right; above, butterfly and before, mark of value I. Below, ROMA. Cr. 184/1b. AE. g. 22.70 mm. 31.00 RR. Very rare and in exceptional condition for the issue. Lovely untouched earthy green patina. GoodVF/AboutEF.