The bulk of the collection consists of bookplates described as "illustrated," which indicates that the bookplate is mounted and accompanied by any one or more of the following materials: a photo or portrait of the bookplate owner or institution, an obituary of biographical note or clipping, a sample signature or autograph. These bookplates include male and female individuals as well as institutions, and are the chief source of plates in the collection owned by notable or historical personalities, such as Lord Byron, J.P. Morgan, H.L. Mencken, and Gouveneur Morris.