474 



Mr. E. C. Hort. 



way, even after thorough cleansing with boiling acid and bichromate 

 solutions. New slides were employed throughout. 



6. The Congo-red emulsion* was made up daily, or on alternate days, 

 with freshly distilled water, this being obtained for each set of experiments 

 by distilling from a clean Jena flask fitted with new glass tubing. The 



Equal Biliary Fission. 



•••• 



Fig. 3.-5. Shiga- Kruse. 



Acid broth + 10 to phen. mixed with broth sub-culture 

 from same. 



emulsion was finally boiled in each case before use. In control films of 



Congo-red alone no organisms could be seen. In this way a dangerous 



source of error, due to mixing with tap water, or with distilled water from 



the ordinary laboratory still, was entirely avoided. 



* In the case of dried films I employ a 1 per cent, solution of HC1 in alcohol in order 

 to avoid distortion of outline, control observations without the acid-alcohol bath showing 

 that, if heat be not employed in drying, the use of a bath of this strength does not cause 

 shrinkage or other distortion. 



