258 SUMMARY OF CURRENT RESEARCHES RELATING TO 



angle. As is seen in the illustration (fig. 62), the apparatus consists of 

 glass and rubber tubing, which are placed inside a test-tube togetber with 

 a suitable amount of culture fluid. The apparatus and contents are steri- 

 lised in the usual way ; but just before using, the culture fluid should be 

 boiled to drive off the absorbed oxygen. When a culture is to be made, 

 the medium is infected in the usual way ; the lips are applied to the 

 projecting piece of rubber tubing, and the culture fluid sucked up into 

 the inner tube somewhere above the top of the lower rubber tubing. 

 This done, the upper tubing is compressed by the fingers (or pinch-cock), 

 and the tubes are then pushed down so as to bend the lower rubber 

 tubing in the way shown in the illustration. The upper ends of the 

 glass tubes should be plugged with cotton wool. The excess of culture 

 fluid left outside the inner tube affoids opportunity of ascertaining 

 whether an organism is an essential anaerobe or aerobe, and also 

 whether it is potentially anaerobic or aerobic. If it be desired to make 

 a cover-glass preparation, the bends of the rubber tubes are straightened 

 out by lifting the glass tube ; the culture fluid then flows out into the 

 outer tube. 



The apparatus has given good results with the tetanus bacillus. 



Procedure for Easily and Eapidly Distinguishing Cultures of 

 Bacillus Typhosus from Bacillus Coli.*— Or. A. Mankowski employs 

 the following coloured nutrient medium for distinguishing between the 

 bacillus of typhoid fever and Bacillus colt communis. The staining mix- 

 ture is made in two solutions, A and B. Solution A is a 1 por cent, 

 solution of caustic potash saturated with acid fuchsin (the pigment is 

 added until the solution assumes a blackish* brown colour). Solution B 

 is a saturated solution of indigo-carmin in water. Two ccm. of solution 

 A, 1 ccm. of solution B, and 22 ccm. of distilled water, are mixed to- 

 gether, and the mixture should be dark blue in colour and of slightly 

 alkaline reaction. To the nutrient medium the solution is added, drop 

 by drop, until the substratum is of a blue or violet hue. The reaction 

 must be neutral. It is sometimes advisable to add a drop of the indigo- 

 carmin solution to the already coloured medium, in order to intensify 

 the blue, and render the reaction of the typhoid bacilli more evident. 

 The typhoid colonies change the blue to a raspberry or carmin-red colour, 

 and the coli colonies to green or greenish-blue at first, and later on dis- 

 charge the colour. The medium used uas agar, with the addition of 

 1/2-1/3 per cent, glucose. 



New Substratum for Isolating Typhoid Bacilli and Bacillus Coli 

 Communis, f — Dr. A. Mankowski recommends a medium, the chief 

 constituent of which is decoction of " mushrooms," for the differential 

 diagnosis c,f Bacillus coli communis and the typhoid bacillus. To the 

 mushroom decoction 1*5 per cent, agar, 1 per cent, pepton, and 5 per 

 cent. NaCl are added. When the mushroom-agar has been boiled, and 

 clarified by means of white of egg, it forms a firm transparent dark 

 brown mass, with neutral reaction and a distinct odour of mushrooms. 

 B. coli grows quickly, and forms a silvery-white firm deposit. The 

 typhoid colonies develope less rapidly, and form a transparent shiny 

 moist streak. In six hours gas-bubbles are visible in the B. coli 



* Centralbl. Bakt. u. Par., 1" Abt„, xxvii. (1000) pp. 21-3. t Tom. cit. pp. 23-4. 



