GIOVANNI d'ANDREA (ca. 1270–1348). Super arboribus consanguinitatis et affinitatis. [Augsburg: Günther Zainer, not after 1473].
The earliest of the fifteenth-century printed books in the Sellers collection, this treatise interprets medieval church doctrine on the blood-relations between men and women that were and were not appropriate for marriage. The author of this fourteenth-century text, a canon lawyer at the University of Bologna, explained that marriages along direct blood lines or as close as third cousins were not permissible by the church. Such prohibition also extended to marriages among in-laws, such as to a deceased spouse's siblings, first cousins, nieces, or nephews. The elaborate woodcuts, each in the form of a "family tree," clarify the allowable levels of relationships. This is one of four recorded copies of this book in the United States.