Trebonianus Gallus, AE Sestertius. Rome. Mule with reverse of Volusian.

IMP CAES C VIBIVS TREBONIANVS GALLVS AVG, laureate, draped and cuirassed bust right.
PRINCIPI IVVENTVTIS, Volusian standing left, holding baton and spear. S-C across fields.

RIC 241 var [Volusian].