4S8 



Pneumonia 



Mori,* and may belong to the same group in which we find Bacillus 

 aerogenes capsulatus. 



Morphology. — Though usually distinctly bacillary in form, the 

 organism is of variable length and when paired sometimes bears a 

 close resemblance to thepneumococcusof Frankel and Weichselbaum. 

 It measures 0.5 to 1.5 ix in breadth and 0.6 to 0.5 ix in length. It 

 frequently occurs in chains of four or more elements and occasionally 

 appears elongated. It is these variations in form that have led to 

 the description of the organism by different writers as a coccus, a 

 bacterium, and a bacillus. It is commonly surrounded by a distinct 

 transparent capsule, hence its name "capsule bacillus" and Bacillus 

 capsulatus mucosus. The organism is non-motile, has no spores, 

 and no flagella. It stains well with the ordinary anilin dyes, but 

 does not retain the color when stained by Gram's method. 



Fig. 172. — Bacterium pneumoniae (modified after Migula). 



Cultivation. — Colonies. — If pneumonic exudate be mixed with 

 gelatin and poured upon plates, small white spheric colonies appear 

 at the end of twenty-four hours, and spread out upon the surface of 

 the gelatin to form whitish masses of a considerable size. Under the 

 microscope these colonies appear irregular in outline and somewhat 

 granular. The gelatin is not liquefied. 



Bouillon. — There is nothing characteristic about the bouillon 

 cultures of Friedlander's bacillus. The medium is diffusely clouded. 

 A pellicle usually forms on the surface and a viscid sediment soon 

 accumulates. 



Gelatin Puncture. — When a colony is transferred to a gelatin 

 puncture culture, a luxuriant growth occurs. Upon the surface a 

 somewhat elevated, rounded white mass is formed, and in the track 



* "Zeitschrift fur Hygiene," 1888, iv, p. 53. 



