Lat. In the civil law. A little book. Libellus supplex, a petition, especially to the emperor, all petitions to whom must be in writing. Libcllum rcscribere, to mark on such petition the answer to it. Li- bcllum agerc, to assist or counsel the emperor in regard to such petitions. Libellus ac- cusatorius, an information and accusation of a crime. Libellus divortii, a writing of di- vorcement Libellus rerum, an inventory. Calvin. Libellus or oratio consulloria, a message by which emperors laid matters before the senate. Id. A writing iu which are contained the names of the plaintiff (actor) and defendant, (reus,) the tiling sought, the right relied upon, and name of the tribunal before which the action is brought. Calvin. In feudal law. An instrument of alienation or conveyance, as of a fief, or a part of it.