186 



Mr. C. Dobell. 



[Feb. 21, 



22. Hammerschlag, " Ueber die Beziehung d. Fibrin fermentes zur Entstehung des 



Fiebers," 'Arch. Exp. Path. u. Pharmak.,' 1891, vol. 27, p. 1. 



23. Freund, H., " Studien iiber d. Fieber d. Blutz. u. Transf.," ' Deutsch. Arch. Klin. Med.,' 



December, 1911, vol. 105, p. 45. 



24. Schultz, "Ueber Transf. b. Mensch. u. Beriick. biol. Vorp.," ' Berl. Klin. Woch.,' 



1910, p. 1407. 



25. Adami, 'The Principles of Pathology,' 1909, p. 446. 



On the Systematic Position of the Spirochcets. 

 By Clifford Dobell, Fellow of Trinity College, Cambridge ; Lecturer at the 

 Imperial College of Science, London, S.W. 



(Communicated by A. Sedgwick, F.R.S. Eeceived February 21, — Read 

 March 28, 1912.) 



This paper is a very brief summary of the chief results of my researches 

 on the Spirochaets and related organisms. I have been occupied with these 

 researches for several years, and I believe that I have now obtained sufficient 

 evidence for it to be possible to form a correct judgment regarding the 

 systematic position of the Spirochaets. 



It is well known that various views of this problem have been taken. 

 Hitherto, three different opinions have been expressed,* and more or less 

 vigorously defended, by different workers. They are : (1) that the Spirochaets 

 belong to the Protozoa ; (2) that they belong to the Bacteria ; (3) that they 

 belong to the Cyanophycea?. The upholders of the first view suppose that 

 the Spirochaets resemble the Flagellata, especially the trypanosomes. Those 

 who support the second view usually regard the Spirochaets as being closely 

 similar to Spirilla. Those who support the third view believe that the 

 Spirochaets show points of resemblance to the spiral forms of Cyanophyceae 

 (Spirulina and Arthrospira).\ 



In view of the existence of these wide differences of opinion and the 

 corresponding mental attitudes of those who have attempted to form a 

 judgment in this matter, I would submit the following statement regarding 

 my own position : — 



* There is a fourth view, which I formerly advocated — namely, that the Spirochaets 

 should be regarded as an independent group of organisms. I no longer hold this view, 

 as further research has shown me that it is incorrect. 



t These three views may be traced back respectively (1) to Schaudinn (1904) ; (2) to 

 Ehrenberg (1833), who placed Spirochosta in his family Vibrionia — the equivalent of the 

 modern Bacteria ; (3) to Cohn (1854), who regarded Spirochceta as a colourless form of 

 Spirulina. 



