I shall let Vallée's book speak for itself. Like the bibliographers who immediately preceded and followed him, Vallée struck out for himself and gave little heed to earlier work. This appears even in his references to bibliographers of bibliographies. In an "Avertissement" he recognizes only three predecessors: Tonnelli in 1782, Petzholdt in 1866, and Sabin in 1872 [the date is wrong]. This is a bad start. Francesco Tonnelli's book[166] is a worthless mixture of a biobibliographical dictionary and a bibliographical handbook. The biobibliographical information is a disorderly collection of notes, referring chiefly, but by no means exclusively, to men whose names begin with the first letters of the alphabet. The bibliographical information is a miscellany of facts about libraries. Tonnelli, who has occasionally buried bibliographies in this rubbish heap, had no intention of writing a bibliography of bibliographies. I cannot guess what use Vallée made of Tonnelli's queer book. If he actually consulted it, he should have objected to its disorderliness and its lack of materials for his needs. Petzholdt's book is, as Vallée says, a classified bibliography of bibliographies made by a competent scholar. It is regrettable that he did not fully accept it as his model. He gives the wrong date for Sabin's book, which began to appear serially in 1875 and was published in 1877. He does not make it clear that he has seen and used it. If we turn to Vallée's references to the works mentioned in this essay, we find nothing to encourage us. He puts Peignot's _Répertoire_, Teissier's edition of Labbé's _Bibliotheca bibliothecarum_, and Labbé's first edition in the _Novae bibliothecae specimen_[167] of 1653 in a section entitled "Bibliographies générales." In other words, he does not consider them to be bibliographies of bibliographies. I cannot see that he cites Labbé's _Bibliotheca bibliothecarum_ at all. Namur's _Bibliographie_ is in a section entitled "Bibliologie" (p. 621) with a mistake in its title. All this indicates, I am afraid, that Vallée did not recognize a bibliography of bibliographies when he saw it. This grievous fault is all the more grievous because he emphasizes in his preface the importance of careful classification.