224 SPECIAL BACTERIOLOGY 



owing to the gelatinous mass being contaminated with various fungi ; to 

 overcome this difficulty heat the cultures continuously for fifteen 

 minutes at 75 C., in order to destroy the fungi. The gelatinous 

 envelopes only develop in cultures on cane or grape sugar media, and in 

 a short time the growth acquires great dimensions. Scheibler considers 

 the gelatinous substance to be dextrin. 



On ordinary Gelatine the growth exhibits no special characteristics. 

 On Gelatine containing grape sugar it is very diagnostic ; consisting in 

 ten to fourteen days of a whitish confluent mass, with slimy, hyaline, 

 gelatinous lumps on the surface. During the first eight days the growth 

 exhibits a dry elastic consistence, but during the next few weeks it 

 becomes softer, moister, finally forming a soft pulp. Individual colonies 

 resemble wart-like balls, sometimes spread out with a puckered film on 

 the surface. 



In Grape Sugar Gelatine Stab Cultures proliferations of various 

 dimensions occur along the inoculation track. 



As already mentioned, the gelatinous substance is only formed in 

 material containing grape or cane sugar. Other carbohydrates tested by 

 Leisenberg and Zopf were found unsuitable. The organism produces 

 Invertin, which splits up the cane sugar. It ferments lactose, maltose, 

 and dextrin, forming lactic acid with a faint evolution of gas. The 

 addition of 3 to 5 per cent, of calcuim chloride to the nutrient medium 

 favours the production of mucus and the fermentation activity of the 

 organism, which is also brisker when oxygen is excluded. 



LEUCONOSTOC INDICUM. 



This organism is the cause of considerable damage to the Java sugar 

 industry. According to Leisenberg and Zopf the only difference 

 between this organism and the Leuconostoc mesenteroides is a slight 

 difference in the optimum temperature at which it develops. 



ASCOCOCCUS BILLROTHII. 



Found by Billroth in putrefying meat infusion. 



Microscopical Appearances. Small cocci, arranged in peculiar 

 colonies, which form a creamy layer upon the surface of liquid media, 

 containing numerous small spherical or oval masses. These masses 

 consist of a jelly-like, extremely resistant envelope, from 10 to 15 (JL thick ; 

 in the interior of the envelope one or more masses of cocci are situated, 

 from 20 to 70 /A or more in diameter. The cocci are closely arranged 

 and united by a firm and scanty intercellular substance. 



Biological Characters. Aerobic. Grows at ordinary room 

 temperature. Produces a strongly alkaline reaction in culture media, 



