The shortened version of the paper presented here will address the various types of marks--graphic and pictorial--made by readers in the margins of twelfth- and early thirteenth-century manuscripts of Roman law. The graffiti and their multiple functions will be discussed in the context of the early teaching and study of law, particularly in Bologna. A scholarly version of this paper will appear in the Festschrift for Richard and Mary Rouse, edited by Christopher Baswell, Sandra Hindman, and Consuelo Dutschke, published by Brepols, and slated to come out in 2010.