244 



BACILLI PATHOGENIC IN MAN. 



of the blood serum is converted into a yellow fluid, 

 at the bottom of which there still lie some pieces 

 of the serum with eaten away, shreddy margins. In 

 nutrient gelatine a spherical layer, 5 10 mm. in 

 diameter, forms at the bottom of the inoculation punc- 

 ture, around the material inoculated, the periphery of 

 which shows fine radiating markings, and the contents 

 consist of liquefied and somewhat turbid jelly. The 

 oedema bacilli grow best in a nutrient jelly which con- 

 tains 1 2 per cent, of grape sugar ; and very charac- 

 teristic cultivations are obtained in test tubes if the 

 gelatine is fluid when inoculated, and the material well 

 distributed through the whole jelly by shaking it before 

 it is allowed to solidify. After two or three days a 

 number of small spheres, J 1 mm. in diameter, and 

 filled with fluid, form in the lower part of the tube, and 

 these show under a low power the radiating marking of 

 the periphery. The colonies extend from the bottom of 

 the vessel to about 2j cm. below the surface. The 

 upper 2J cm. of the gelatine remain completely unal- 

 tered. By pouring on oil, 

 introduction of carbonic 

 acid, &c., one can arti- 

 ficially raise the upper 

 limit within which visible 

 colonies are formed.* 



The best temperature 

 for growth is about that 

 of the human body ; but 

 luxuriant growth also oc- 

 curs at 18 20 C., es- 

 pecially in jelly contain- 

 ing sugar. Spore forma- 

 tion has also been observed 



Fig. 68. Cultivations of the bacilli , , -. , , 



of malignant oadcma in gelatine, at this temperature, but 



it occurs more readily and 



plentifully at the higher temperature. In the animal 

 body only bacilli and threads are found immediately after 



* After observations by Dr. Liborius in the Hygienic Institute at 

 Gottingen. 



