PATHOGENIC ANAEROBIC BACILLI. 547 



190. BACILLUS PHLEGMONES EMPHYSEMATOS^E (E. Frankel). 



Obtained by Frankel (1893) from four cases of "gas phlegmon." 



Morphology. Short, thick bacilli, with round ends, about as thick as 

 the anthrax bacillus, usually united in pairs ; long filaments are seen in gela- 

 tin cultures, and in the tissues of infected guinea-pigs. 



Biological Characters. An anaerobic, non-motile, liquefying bacillus. 

 Spores are occasionally seen in agar cultures ; these are spherical and lo- 

 cated in the slightly swollen extremities of the rods. In glucose-agar (one 

 per cent glucose) plates, in an atmosphere of hydrogen at 37 C., gas bub- 

 bles are seen upon and below the surface; these may have a diameter of 

 one centimetre, and small bubbles are often attached to the larger ones. In 

 other places the agar is split open ; in others still, colonies are developed 

 without the formation of gas ; these are round, with a dark-brown centre 

 and paler margin. In stick cultures in agar containing one per cent of 

 glucose the growth, at 37 C., is abundant at the end of twenty-four hours 

 all along the line of puncture ; the agar is split up by gas, and bubbles often 

 accumulate on the surf ace. In gelatin cultures, in an atmosphere of hydro- 

 gen at the end of two or three days, small, round, brownish-yellow, slightly 

 granular colonies are developed, which later appear to lie in an air bubble. 

 In gelatin stick cultures growth is first seen one to two centimetres below the 

 surface ; after several days spherical colonies are developed along the line 

 of puncture, and at times liquefaction is seen, while at others gas bubbles 

 are developed. Upon blood serum, in hydrogen, an abundant development 

 occurs with formation of gas ; these cultures give off a fetid odor. In milk 

 coagulation occurs, but no gas is developed. The bacillus dies out in agar 

 cultures within two or three days, unless they are preserved in hydrogen. 

 In gelatin cultures it survives for several months. 



Pathogenesis. In guinea-pigs subcutaneous inoculation gives rise to the 

 development of a gas phlegmon, and usually to the death of the animal. 

 Not pathogenic for mice or for rabbits when injected into the circulation. 



NOTES RELATING TO THE PREVIOUSLY DESCRIBED ANAEROBIC 



BACILLI. 



Tetanus Bacillus. Brieger and Cohn, in investigations (1893) relating to 

 the toxic products of the tetanus bacillus, have arrived at the following re- 

 sults : The cultures were made in veal bouillon containing one per cent of 

 peptone and one- fifth per cent of chloride of sodium. Large quantities of 

 the cultures in this medium were filtered through porcelain filters. The 

 active substance was precipitated from the filtrate by means of a saturated 

 solution of ammonium sulphate. By adding this salt in excess the precipi- 

 tate is made to rise to the surface and is skimmed off with a platinum spatula. 

 The liquid is removed by placing this upon porous porcelain plates and the 

 crude toxin is dried in a vacuum. It still contains 6.5 per cent of ammo- 

 nium sulphate. The tetanus bouillon after filtration is said to be fatal to 

 mice in the dose of 0.00005 cubic centimetre. A litre of this bouillon gave 

 about one gramme of the dried precipitate, which produced characteristic tet- 

 anic symptoms and death when injected into mice in the dose of 0.0000001 

 gramme. Kitasato, in his experiments, had previously obtained a tetanus 

 bouillon which was five times as toxic as that used by Brieger and Cohn in 

 their experiments, and which killed mice in the dose of 0.00001 cubic centi- 

 metre. The dried precipitate obtained by Brieger and Cohn contained vari- 

 ous impurities, including a certain amount of ammonium sulphate, but was 

 found to kill susceptible animals in the proportion of 0.0000066 gramme per 

 kilogramme of body weight. 



It was purified without loss of toxic power by placing it in a dialyzer in 

 running water for from twenty-four to forty-eight hours, after which it was 



