330 BACTERIA. 



information, even in the case of dried false membranes sent from a distance 

 wrapj)ed in linen or blotting-paper. They also hold that where improve- 

 ment is taking place, the specific bacilli become less numerous, the other 

 microbes increasing in number, and that this may be followed day by day 

 with a microscope, the course and prognosis of the disease being indicated 

 by the changes that are met with. They also hold that at the beginnir^ of 

 a case of diphtheria it is possible to predict a favourable issue from the 

 presence of a small number only of the specific bacilli, and a large number 

 of other forms, and they also believe that some of the micro-organisms met 

 with under these conditions interfere with the growth and activity of the 

 specific bacillus. 



The Klebs-Loffler bacillus cannot be cultivated outside the 

 body on peptone meat gelatine, as it will not grow sufficiently 

 rapidly at the room temperature to outpace the putrefactive 

 organisms which accompany it ; it was, therefore, found 

 impossible to make plate cultivations in order that the 

 different forms might be separated. 



By mixing the membrane with boiled distilled water and 

 allowing drops of the mixture to trickle over the surface of 

 solidified blood serum, Loffler succeeded in obtaining pure 

 cultivations. Wyssokowicz, using agar instead of gelatine 

 for making plate cultivations, and incubating at 35° C, was 

 able, on a small percentage of his plates, to obtain pure 

 cultivations of the characteristic diphtheria bacillus ; most 

 ■ of his plates, however, were overgrown with putrefactive 

 and other non-pathogenic organisms. 



To obtain a somewhat purer inoculating material, put a scrap of mem- 

 brane between blotting-paper, or on a cover glass in a test tube, allow it to 

 dry, and then heat to a temperature of 98° C. for a whole hour — a tempera- 

 ture which few ordinary organisms can withstand for even a less time than 

 this — so that, when the dried material from a cover glass so treated is 

 inoculated on solidified blood serum, a very pure cultivation is usually 

 obtained. 



Roux and Yersin adopted a simpler method. They used a 

 platinum needle beaten out at the end to form a kind of spa- 

 tula ; on this they took a particle of the false membrane from a 

 case of diphtheria and then made stroke cultivations on the 

 surface of the solidified blood serum, using the same needle 

 without re-charging for some half-dozen tubes. When these 

 are incubated at from 33° to 35° C. the baciUi rapidly make 

 their appearance ; they are visible at the end of twenty hours 

 and have a characteristic appearance in forty-eight hours. 

 This rapid growth is very characteristic of the diphtheria 



