« GRANULE-CLUMPS > AND SPIROCHAETES 51 



between the results ol" my confrères and those of myself. 

 I sliciU hère only mention briefly some récent observations 

 which hâve strengthened my personal conviction that some, 

 at ail events, ot thèse disputed granule-clumps are derived 

 from spirochaetes and are able subsequently to develope again 

 into spirochaele form. 



In my earlier work the method employed was to infect 

 simiiltaneously a number of ticks of the same âge by permit- 

 ting them to feed on a heavily infected mouse. The ticks were 

 then divided into two or three batches, which were kept under 

 différent conditions of température and moisture. Every day, 

 or every 2 or 3 days subsequently, one of each batch of ticks 

 was caret'ully dissected and a close examination was made of 

 the différent organs, tissues and lluids for the présence of 

 spirochaetes and of granules ; careful records were kept of the 

 results and sketches made of anything of interest. The micro- 

 scopical examination was in part carriedout on the fresh fluids 

 or on pièces of tissue teased out in saline solution, but chietly 

 by observation of dried film préparations, fixed and stained by 

 mv own modification of Romanowskv's method. In the latter 

 case the chro matin staining w-as carried to a high degree of 

 intensity, the films being fmally treated w4th 60 p. 100 Alcohol 

 to dissolve off ail traces of deposit of the stain. I note that 

 MM. Marchoux et Couvy are of opinion that the Chromatin 

 method of staining may fait to colour thin or délicate spiro- 

 chaetes and tliey recommend as a better method the use of 

 Gentian Violet. 1 find however that my method demonstrates 

 Treponema pallidum readily in films in which thèse délicate 

 organismsare quite untouched by Gentian Violet and, further, 

 it permits of the ready récognition of Spirochaeta duttoni in 

 tissues such as muscle fibres wdien Gentian Violet fails to 

 disclose them. 



Subsequently to the séries of observations to which my 

 previous papers referred, the dark-ground method of illumi- 

 nation came into more gênerai use and I hâve since repeated 

 some of my earlier experiments, utilising this method of exa- 

 mination as a control and supplément to the staining method 

 mentioned above, and I bave found it of great service, particu- 

 larly in the détermination of motility in the spirochaetes. The 



