I ASHBURN AND CRAIG. 



Spotted fever of Montana; Eocky Mountain fever; tick fever; Pyrop- 

 lasmosis hominis (Wilson and Ch owing) ; tick fever of the Eocky 

 Mountains; Eocky Mountain spotted fever. 



As so-called spotted fever has been described as occurring in various districts 

 of the Rocky Mountain region, and as it has not been determined that the same 

 infection is identical in all those parts, the term spotted or tick fever of Montana 

 will be used in this paper, the disease referred to being that occurring in western 

 Montana, particularly in the Bitter Root Valley, in Missoula and Ravalli 

 Counties. 



II. INTRODUCTION. 



For many years hedani or tsutsugamushi disease has been an annual 

 subject of the most active and painstaking investigation on the part 

 of Japanese physicians and the Japanese Government. 



One of the leading investigators of late years is Dr. M. Miyajima of 

 the Institute- for Eesearches of Infectious Diseases, of Tokyo. Dr. 

 Miyajima had read of the work of Wilson and Chowning, Anderson, Stiles 

 and others on the study of "spotted" or "tick fever" in Montana and as 

 he had found so many points of similarity in the two diseases, he thought 

 it quite possible that they were the same. Consequently, when he 

 came to Manila as a representative of his Government to the Philippine 

 Islands Medical Association, he was desirous that we should visit Japan 

 at the proper season and determine, if possible, whether or not such is 

 the case. Thanks to the' representations of Dr. Miyajima and the 

 liberal view taken of the matter by Major-General Leonard Wood,, the 

 Acting Surgeon-General and the War Department, we were ordered to 

 Japan; and this report is based on the observations concerning tsutsuga- 

 mushi disease made on that trip and those of one us (Ashburn) in 1904 

 and 1905 on the cases of spotted fever occurring during those years in 

 the Bitter Boot Valley in Montana. 



The specific point we were to endeavor to determine, and which we 

 think we have determined, was the question of the identity or noniden- 

 • tity of the two diseases and the greater amount of emphasis will be laid 

 on that point in this report. 



However, as both diseases are so closely restricted in their locality, 

 and so are necessarily unknown to the very great majority of medical 

 men, a brief account of each will be given and an effort will be made 

 to place them side by side, so that the resemblances and differences may 

 be brought out more strikingly. The descriptions to be given are based 

 on personal observations of some twenty-two cases of "spotted fever" 

 and seven cases of tsutsugamushi disease, as well as on the writings of 

 others who have studied one disease or the other more carefully than 

 we could. 



Both infections are still subjects of earnest and careful investigation by 



