Which preposition to use with prelections

of Occurrences 1%

Small wonder that I was backward with my colleging, and at an age when most lads are buckled to a calling was still attending the prelections of the Edinburgh masters.

On Occurrences 1%

And now, as we have the whole morning before us Let us go in, if you make no objection, And listen awhile to a learned prelection On Marcus Aurelius Cassiodorus.

Which preposition to use with  prelections