[ULPIANUS libro quadragesimo tertio ad edictum. ] §50.16.194.prInter 'donum' et 'munus' hoc interest, quod inter genus et speciem: nam genus esse donum Labeo a donando dictum, munus speciem: nam munus esse donum cum causa, ut puta natalicium, nuptalicium.
[ULPIANUS in the forty-third book on the Edict.] Between 'donum' and 'munus' there is this difference, which is between genus and species: for Labeo says that 'donum', named from 'donando', is the genus, and 'munus' is the species: for 'munus' is a 'donum' with a cause, such as a birthday present, a wedding present.