Quando dies usus fructus legati cedat
(When the Legacy of an Usufruct Vests.)
1Ulpianus, On Sabinus, Book XVII. Although an usufruct consists of enjoyment, that is to say, in some effort exerted by him who enjoys and uses the right; still, it vests but once, and it is different from where something is bequeathed every month, or every day, or every year; for then the legacy vests daily, monthly, or yearly. Wherefore the question may arise, where an usufruct is bequeathed to anyone, for every day, or for every year, does it vest but once? I think that it does not, but as many times as it is mentioned, so that there are several legacies. Marcellus approves this opinion in the Fourth Book of the Digest, where an usufruct is bequeathed to anyone for alternate days. 1Therefore, if an usufruct is bequeathed which cannot be enjoyed every day, the bequest will not be invalid, but it will vest on the day when it can be enjoyed. 2An usufruct, however, and likewise an use, will not vest before the estate is entered upon, for an usufruct is not created until someone can immediately enjoy it. According to this rule, if the usufruct is bequeathed to a slave forming part of an estate, Julianus holds that, although other legacies may be acquired by the estate, in the case of an usufruct we must wait for the person of the owner who can use and enjoy the same. 3Moreover, if an usufruct is bequeathed from a certain day, it will not vest until the day arrives; for it is established that an usufruct can be bequeathed from a certain time or until a certain time. 4Not only does an usufruct not vest before the estate is entered upon, but a right of action based upon usufruct does not do so either; and the same rule applies where an usufruct is bequeathed after a certain day; hence, Scævola says that a party who brings an action before the day of the usufruct will gain nothing; although any legal procedure which is instituted before the proper time is void.