This number of the Handbuch contains a masterly article by Landsteiner on poliomyelitis. If all writers selected their material as critically and pruned it as relentlessly as he has done, the various reviews and summaries of scientific work would not be swollen to their present monstrous proportions and the harried reader in every land would not be smothered under a multitude of irrelevant facts and verbosity. The other articles in this number are sound and scholarly but of a more familiar type. The printer is apparently giving more attention to the correct reproduction of names of authors and titles of papers in other languages than German. The blunders so frequently observed in the bibliographies of earlier articles are not conspicuous in this issue.