LABORATORY MANUAL IN GENERAL MICROBIOLOGY PREPARED BY THE LABORATORY OF BACTERIOLOGY AND HYGIENE MICHIGAN AGRICULTURAL COLLEGE - - 1916 -- PREFATORY NOTE LABORATORY instruction in bacteriology at the Michigan Agricultural College developed under the direction of Dr. C. E. Marshall. This laboratory guide represents the accumulated efforts of instructors working for a period in excess of a decade. To Assistant Professor L. Zae Northrup is due the credit for collecting and arranging the material presented as well as for preparing de novo many of the experiments and much of the supplementary matter. She has been assisted by Mr. W. L. Kulp. Dr. E. T. Hallman and Dr. L. R. immelberer have taken the responsibility for arranging the exercises relating to immunity, serum therapy and pathologic bacteriology. Great praise is due Dr. F. H. H. Van Suchtelen for introducing many new features into the laboratory work during the academic year 1912-13, and also Dr. Otto Rahn for his several years of admirable effort immediately preceding. Others whose influence has been felt in creating this guide and to whom credit is due are Professors W. G. Sackett, S. F. Edwards, L. D. Bushnell, C. W. Brown and W. H. Wright. While some claim to originality may be made for- this laboratory guide, it is to be expected that much of the material herein has been presented in various other manuals and perhaps in better form in many instances. The greatest effort has been made to make this a laboratory guide to General Microbiology, leaving the particular fields of dairy, soil, water, medical and other phases of bacteriology to special guides already in print or at present projected. The presentation of this manual to the public i in . no - .. way an intimation that the special fields have not been admirably dealt with by others. The subject matter given under Part I of this manual is primarily for the purpose of giving a working knowledge of laboratory methods used in the study of microorganisms. Molds, yeasts and bacteria are taken up in the order of their comparative sizes.and studied as to their identification by morphological and cultural methods. It is presupposed that the student has a knowledge of these microorganisms acquired from preceding lectures in microbiology. Part I1 consists of exercises demonstrating the various physiological activities of microorganisms. Part I11 deals with applied microbiology. After the student has familiarized himself with the ordinary tools and technic, etc., as dealt with in Parts I and 11, it is not neces- - sary that he be burdened with minute, detailed instructions. We have had this in mind in preparing Part 111. No attempt has been made to compile an exhaustive list of exercises the aim has been only to cover a wide range of activities under each different subject. In many cases, exercises have been taken directly, with few or no modifications, from laboratory manuals already in print. Credit has not been given directly the list of references, however, includes all books from which material has been taken. The purpose of this laboratory manual is to make the student more independent. Practically all directions for work to be done are contained in-it for this reason the work as assigned from day to day should be read-over carefully before beginning an exercise and then followed step by step. Any desirable changes in directions may be indicated by the instructor. WARD GILTNER, Head of Department, EAST LANSING, MICH. Sept. 1, 1915. CONTENTS PART I GENERAL MORPHOLOGICAL AND CULTURAL METHODS PAGE .............................. ............................................... .......... ............................................ .............................. Exercise 1 . Cleaning Glassware 1 Sterilization 5 Exercise 2 ...