The foregoing details about the first book in Gesner's _Pandectae_ make clear Gesner's skill in organization and classification as well as the place that the bibliography of bibliographies had in his scheme. They give some notion of sixteenth-century scholarship and explain why Gesner's _Pandectae_ failed to be continued or revised and, more especially, why his bibliography of bibliographies has not been noticed. Even A. G. S. Josephson, who had a very sharp eye for bibliographies of bibliographies concealed as chapters in subject indexes, did not come upon Gesner's work. Josephson's study will be mentioned in its proper place at the end of this essay. Gesner's subject bibliography was not appreciated fully because it contained many references to classical sources and did not give a comprehensive account of contemporary writings. Although Gesner's classification was logical and although he adhered with remarkable care to the categories that he set up, no one but Gesner himself could make additions to the book or revise it. It remains to say a word about the relation of the _Pandectae_ to the book of which it forms a part. Gesner published four volumes--the _Bibliotheca universalis_ of 1545, the _Pandectae_ of 1548, the _Partitiones_ of 1549, and the _Appendix_ of 1555--that are ordinarily regarded as a single work. The _Bibliotheca_ and the _Appendix_ constitute a biobibliographical dictionary. The _Pandectae_ and the _Partitiones_ are a subject index that lacks a promised section on medicine. The dictionary and the index have no close relations to each other, except to the degree that the dictionary gives additional information about books cited by authors' names in the index. In Gesner's situation a modern scholar would have distributed according to subjects the slips that he had made for his biobibliographical dictionary and would thus have obtained a subject index almost immediately. Gesner did not proceed in this way, but undertook and completed the subject index as a virtually independent work.