As a students' laboratory guide, which is daily standing the test of use, this work can be cordially recommended. It does not, as the author states in his preface, give full consideration to certain subjects, like the questions of immunity and the individual pathogenic bacteria, as these subjects are treated by him, in his course, in lectures that are altogether distinct from the laboratory work. It contains, however, in its opening chapters, the necessary general information for laboratory work, and the concluding chapters describe special methods and tests suitable for advanced student work. The value as a student's manual is enhanced by the blank pages opposite the specific descriptions for notes, illustrations, etc.