Among the incunabula in the John Hay Library of Brown University are two quarto editions of Horace's Opera, with comment by Cristoforo Landino, one published in Florence in 1482 “per Antonium Miscominum,” the other in 1483 in Venice “per Joannem de Forlivio et socios,” the latter edition probably pirated from the former. Both volumes contain holograph annotations by Pomponio Leto, by Bernardo Tasso and by Torquato Tasso; and both volumes, so far as I can ascertain, have been overlooked by scholars both in Italy and in this country. I have, therefore, undertaken to study part, at least, of this material.