IN SUSCEPTIBLE ANIMALS. 439 



acters, as expressed by the behavior of these bacteria in bouillon con- 

 taining- dextrose, saccharose, and lactose, which I think will serve as a very 

 important group character, differentiating such groups sharply from the 

 colon group. I would therefore suggest that for the present all bacteria 

 whose size approximates that of this group, which do not liquefy gelatin, and 

 whose fermentative properties are the same as those described for this group, 

 should be ranged under it. Future investigations into the biochemical char- 

 acters* of these varieties or sub-species may reveal other differential charac- 

 ters, but the time has not yet come when such laborious work will be under- 

 taken o a sufficiently extensive scale to be of any service in differentiating 

 varieties and sub-species." 



Selander in 1890, and Metschnikoff in 1892, have reported a rapid increase 

 in virulence of the bacillus of hog cholera by successive inoculations in 

 rabbits* or pigeons. Moore (1894) has shown that this is a mistake, and that 

 the bacteriologists named probably did not experiment with cultures of the 

 hog-cholera bacillus, as they supposed, but that their experiments were 

 made with the bacillus of swine plague Bacillus septicaemias hemprrhagi- 

 cae which when passed through a series of rabbits attains a notable increase 

 in pathogenic virulence. 



In a recent article, Klein, of London (1895) says: " The bacillus of 

 English swine plague, which I described in 1884, in Virchow's Archiv, as 

 shown by Smith and Welch, is identical with the bacillus of American hog 

 cholera." 



64. BACILLUS OF BELFANTI AND PASCAROLA. 



Synonym. Impf tetanusbacillus. 



Obtained by Belfanti and Pascarola (1888) from the pus of wounds in an 

 individual who succumbed to tetanus. 



Morphology. Bacilli with rounded ends, sometimes so short as to resemble 

 micrococci ; resemble the Bacillus septicaemiae haemorrhagicae (fowl cholera). 



Stains with the usual aniline colors and also by Gram's method. The 

 ends are commonly more deeply stained than the central portion. 



Biological Characters. An aerobic and facultative anaerobic, non- 

 liquefying, non-motile bacillus. Spore formation not observed. Grows in 

 the usual culture media at the room temperature. Upon gelatin plates yel- 

 lowish-gray, finely granular, spherical colonies with smooth outlines are 

 developed. In gelatin stick cultures, at 18 to 25 C M at the end of twenty- 

 four hours small, spherical colonies are developed along the line of punc- 

 ture, which are isolated or closely crowded; upon the surface a rather thin, 

 shining, grayish- white, iridescent, circular layer is formed ; gas is given off 

 which has not a disagreeable odor. Upon the surface of agar elevated, 

 shining, gray colonies develop along the impfstrich, or a gray, shining band 

 is formed which increases in thickness but not in breadth usually less than 

 one-half centimetre broad. Old cultures give off an acid odor. Upon blood 

 serum a thin, white layer is developed along the line of inoculation. Upon 

 potato a thin, white, varnish- like layer is formed. 



Pathogenesis. Very pathogenic for rabbits, guinea-pigs, white mice, and 

 sparrows. Not pathogenic for chickens, pigeons, or geese. 



05. BACILLUS OF SWINE PLAGUE, MARSEILLES. 



Synonyms. Bacillus der Schweineseuche, Marseilles (Rietsch 

 and Jobert) ; Bacillus der Frettchenseuche ferret disease (Eberth 



