[POMPONIUS libro quinto ad Sabinum. ] §30.1.22.prSi grege legato aliqua pecora uiuo testatore mortua essent in eorumque locum aliqua essent substituta, eundem gregem uideri: et si deminutum ex eo grege pecus esset et uel unus bos superesset, eum uindicari posse, quamuis grex desisset esse: quemadmodum insula legata, si combusta esset, area possit uindicari.
[POMPONIUS, Book 5 of Commentary on Sabinus.] If a flock is bequeathed, and some beasts die while the testator is still alive and others are substituted in their place, it is considered to be the same flock; and if the livestock of that flock is so diminished that only a single ox survives, this one can be claimed, although the flock has ceased to exist: just as, when an apartment building has been bequeathed, if it is burned down, the site can be claimed.