on."[60] Jodocus a Dudinck had a very good eye for opportunities in the bibliographical field. He announced a general treatise on libraries[61] and both a bibliography of the Virgin Mary and an account of the places associated with her.[62] No one has even seen any of Dudinck's books, but the fact that books on all these subjects were written by other hands within a generation shows his ingenuity and judgment as a bibliographer. Nothing appears to be known about Dudinck beyond what Valerius Andreas has to say. He was a priest in a small village in the Rhineland, "multae vir lectionis." Ten years after the announcement of Dudinck's book Philip Labbé (1607-1667) printed a bibliography of bibliographies as a supplement to his _Novae bibliothecae specimen_ (1653).[63] He seems to have regarded this later as a separate publication and has caused some confusion by doing so. On its separate title page the date of this supplement is 1652, but the supplement does not appear to have been issued separately and the title page of the book bears the date 1653. This bibliography of bibliographies is entitled: "Supplementum novae bibliothecae, sive speciminis antiquarum lectionum, coronis libraria. Hoc est, Bibliotheca Bibliothecarum, & Catalogus Catalogorum, Nomenclatorum, Indicum, Elenchorum, &c. quibus Scriptores in quavis arte & professione praecipui, &c. libri ferme omnes, partim editi, partim inediti repraesentantur." Here Labbé has defined the proper contents of a bibliography of bibliographies. He has included very few inappropriate titles in his list of nearly three hundred separately published bibliographies, bibliographies that were still in manuscript, and bibliographies published in non-bibliographical works. There are very few examples of the last category. He is careful about his work. For example, he cites a manuscript biobibliographical dictionary by Alfonsus Ciaconius (Alfonso Chacón, 1540-1599) and gives his authority in Antonio Possevino, _Apparatus sacer_ (Cologne, 1608). Chacón's dictionary was not printed until 1731, and then only as a fragment. Labbé knows Alfonso Barvoet's catalogue of manuscripts in the Escorial; Alfonso García's list of famous Spaniards; Ambrosio Gozzi's biobibliographical dictionary of Dominicans; Andreas Quercetanus's (André Duchesne, 1584-1640) bibliography of French history (three editions are cited); autobibliographies like "Index librorum F. Angeli Rochensis. Romae 1611"; national bibliographies like that for France by Antoine du Verdier; and a classical miscellany like Athenaeus, _Deipnosophistae_, which scholars then regarded as a bibliography. In other words, Labbé has named examples of varieties of bibliographies that we now recognize. Although he mentions a publisher's catalogue (which he has not seen), he seems doubtful about its pertinence to the task. He comments, for example, on a collective volume in the De Thou library that contained catalogues issued by Plantin, Froschauer,