A picture of a Roman coin showing a lighter sort of Roman galley, or rowing-boat. The rowers here appear to be wearing helmets, so presumably are soldiers rather than slaves. Compare with Fig. 94.
dirtyoldcoins.com has a picture of a similar coin, from about A.D. 132 – 135, identified as RIC 209, BMC 546, C 653 Denarius Obv: HADRIANVSAVGVSTVS - Bare head left. Rev: FELICITATIAVG Exe: COSIIIPP - Galley left. c.132-135 (Rome).