vi PREFACE. 



Medical and Surgical Diseases, they now venture to express their 

 willingness to supply materials for making artificial cultures, and to 

 report on material sent to them for examination. 



They desire to record their sense of indebtedness to the officials 

 of the German Imperial Board of Health Laboratories, to whose 

 assistance and courteous interest they owe their first acquaintance 

 with many of the facts contained in this section. 



They have also to acknowledge the valuable assistance of Mr. J. 

 Tatham Thompson, F.R.M.S., whose exact delineations of microscopic 

 and naked eye appearances have greatly enhanced the value of the 

 descriptive portions of the work ; and at the same time they heartily 

 thank Mr. W. B. Mackay, M.B., M.R.C.S., for several valuable 

 drawings. 



The drawings not initialed are copied from photographs taken for 

 the purpose. 



University of Edinburgh, 

 June 1885. 



