362 



TYPHOID FEVER 



{vide p. 108), the bacilli are seen to possess many long wavy 

 flagella which are attached all along the sides, and to the ends 

 (Fig. 107).- They are more numerous, longer, and more wavy 

 than those of the b. coli. 



Cfiaracters of Culture. — Generally speaking, on artificial 

 media growths of the b. typhosus appear less dense than those 

 of the b. coli. Stab cultures in peptone gelatin give a somewhat 



A. Stab culture of the typhoid bacillus in gelatin, five days' growth. 



B. Stroke culture of the typhoid bacillus on gelatin, six days' growth. 



C. Stab culture of the bacillus coli in gelatin, nine days' growth; the gelatin 



is split in its lower part owing to the formation of gas. 



characteristic appearance. On the surface of the medium growth 

 spreads outwards from the puncture as a thin leaf-like film or 

 pellicle, with irregularly wavy margin (Fig. 108, A). It is semi- 

 transparent and of bluish-white colour. Ultimately this surface 

 growth may reach the wall of the tube. Xot infrequently, how- 

 ever, the surface growth is not well marked. Along the stab 

 there is an opaque whitish .line of growth, of finely nodose ap- 

 pearance. There is no liquefaction of the medium. In stroke 



