240 THE ACUTE PNEUMONIAS 



which has been applied. It must, however, be stated that the 

 growth of the organism on gelatin does not so frequently corre- 

 spond to this description as was formerly supposed to be the 

 case. Occasionally bubbles of gas develop along the line of 

 growth. There is no liquefaction of the medium. On sloped 

 agar the pneumobacillus forms a very 

 white growth with a shiny lustre, which, 

 when touched with a platinum needle, is 

 found to be of a viscous consistence. In 

 cultures much longer rods are formed than 

 in the tissues of the body (Fig. 68). On 

 the surface of potatoes it forms an abun- 

 dant moist white layer. It is non-motile. 

 Friedlander's bacillus has active ferment- 

 ing powers on sugars, though varieties 

 isolated by different observers vary in the 

 degree in which such powers are possessed. 

 LgBgJ It always seems capable of acting on 



dextrose, lactose, maltose, dextrin, and 

 rnannite, and sometimes also on glycerin. 

 The substances produced by the fermenta- 

 tion vary with the sugar fermented, but 

 include ethylic alcohol, acetic acid, Isevo- 

 lactic acid, succinic acid, along with hydro- 

 gen and carbonic acid gas. The amount 

 of acid produced from lactose seems only 

 exceptionally sufficient to cause coagulation 

 of milk. With regard to indol formation 

 the results of different observers vary. 

 Here, as with other reactions, it is to be 

 ^i^^r noted that only strains isolated from cases 



of pneumonia are to be taken into account. 

 FIG. 67. Stab culture of T , -i 1 ,-, , .-, -, . 



Friedlander's pneumo- IS said by some that the bacillus IS 

 bacillus in peptone identical with an organism common in sour 

 gelatin, showing the milk and also a norma l inhabitant of the 

 nail-nke appearance : , . , , , 



ten days' growth, human intestine, namely, the bacterium 

 Natural size. lactis aerogenes of Escherich. It is closely 



allied to the b. coli group. 



The Occurrence of the Pneumobacteria in Pneumonia and 

 other Conditions. Capsulated organisms have been found in 

 every variety of the disease in acute croupous pneumonia, 

 in broncho-pneumonia, in septic pneumonia. In the great 

 majority of these it is Fraenkel's pneumococcus which both 

 microscopically and culturally has been found to be present. 



