VI 



THE ACTINOMYCETES, VOL. I 



tific career, I came in touch with a group of 

 microorganisms that were to occupy a major 

 part of my future scientific hfe. The final 

 year of my undergraduate studies of these 

 organisms was followed by three years of 

 graduate work,t and by many more years 

 as scientific assistant and finally as micro- 

 biologist at the New Jersey Agricultural 

 Experiment Station. 



The following treatise is, in part, a sum- 

 mary of these investigations carried out for 

 nearly half a century, mostly in the labora- 

 tories of Rutgers University, first at the 

 College of Agriculture and Experiment Sta- 

 tion, and more recently at the Institute of 

 Microbiology. In a larger sense, however, I 



t "Proteolytic Activities of the Soil Fungi and 

 Actinomycetes," Sehnan A. Waksman, Ph.D. 

 Thesis, University of California, December 1917 

 (J. Bacteriol. 3: 475-492, 509-530, 1918). 



wish to give credit to the many other investi- 

 gators who, by their careful and exhaustive 

 studies, have so far advanced our knowledge 

 of the actinomycetes during this first half of 

 the Twentieth Century. 



In the preparation of this volume, I have 

 drawn freely from the various theses sub- 

 mitted by candidates for their Ph.D. degrees, 

 working under my direct or indirect super- 

 vision. I wish to acknowledge the assistance 

 of my colleagues and collaborators, notably 

 Dr. Ruth E. Gordon, Dr. Hubert A. Le- 

 chevalier, ]\Ir. Robert A. Day, and Mrs. 

 Herminie B. Kitchen. I also wish to thank 

 Dr. C. W. Emmons, of the National Insti- 

 tutes of Health, for reading Chapter 17, and 

 Dr. L. A. Schaal, of the U. S. Department 

 of Agriculture, for reading Chapter 18. 



Selman A. Waksman 



