From BiblePortal Wikipedia

Collatio [1]

is a term for the reading from the lives or collationes of the fathers, which St. Benedict (Regula, c. 42) instituted in his monasteries before compline. Such compilations as the collationes of John Cassian were read. Ardo Smaragdus, however, says that this service was called collatio because the monks questioned each other on the portions to be read. The Benedictine practice is to hold this service in the church, and this is probably in accordance with the founder's intention, for he evidently contemplated the collation being held in the same place as compline (Ducange, s.v.).