from
Bouvier's Law Dictionary, Revised 6th Ed (1856)
HAERES civil law. An heir, one who succeeds to the whole inheritance.
2. These are of various kinds. 1. Haeres natus, an heir born; the heir
at law: he is distinguished from, 2. Haeres factus, or an heir created by
will, a testamentary heir, to whom the whole estate of the testator is
given. 3. Haeres fiduciarius, an heir to whom the estate is given in trust
for another. Just. 2, 23, 1, 2. Haeres-legitimus, a lawful heir; this is one
who is manifested by the marriage of his parents; haeres legitimus est quem
nuptiae demonstrant; haeres suus, one's own heir, a proper heir;
descendants. Just. 3, 1, 4, 5.