A second annual survey of the current output of bibliographies is the _Bibliographie des Bibliotheks- und Buchwesens_, edited by Adalbert Hortzschansky from 1905 to 1925 with an interruption of eight years from 1913 to 1921. This supplement to the _Zentralblatt für Bibliothekswesen_ had a longer and more successful life than its predecessor. It surveyed all publications that fell within the field of the journal and therefore included much more than the bibliography of bibliographies. In 1926 it became an independent publication with a slightly different title but with no change in the subjects reported upon. This _Internationale Bibliographie des Buch- und Bibliothekswesens_ continued to be issued down to the outbreak of war in 1939. An enterprise of somewhat similar scope, the _Literarisches Beiblatt der Zeitschrift_ (later: _zum Jahrbuch_) _des deutschen Vereins für Buchwesen und Schrifttum_ began to appear in 1924 and continued to 1939. Since these annual surveys include more than the bibliography of bibliographies, I shall not discuss them further. Three reviews of contemporary bibliographical work have appeared during the last twenty-five years. One of them is limited to bibliographies of a particular kind, and the other two are more or less complete periodical surveys of bibliographical writings. I mention them here as the last examples of the development of periodical bibliographies of bibliographies and as a means by which one can estimate the task of any modern compiler of a bibliography of bibliographies. The first of these, the _Index bibliographicus_, which first appeared in 1925, offers an interesting example of specialization within the field of bibliographies of bibliographies. The _Index bibliographicus_ is general in scope but cites only bibliographies of bibliographies that appear as current serial publications. In the six years between its first appearance in 1925 and its republication in enlarged and improved form in 1931 the number of currently appearing serial bibliographies rose from 1025 to 1900. Some of these had been overlooked in 1925, but many of the additions concerned bibliographies of bibliographies that had been established during the six years between the two editions. The _Index bibliographicus_, which was compiled with the assistance of the League of Nations, assumed a more definitely international and cooperative aspect when Joris Vorstius joined Marcel Godet as editor.[182] A third edition of the _Index_ made by Theodore Besterman in 1952 is still larger than either of its predecessors.