490 



A MANUAL OF BACTERIOLOGY 



Friedlander's Pneumo -bacillus 



This organism, already referred to above in the general 

 discussion of pneumonia, is one of the capsulated bacilli 

 (p. 313). 



Morphology. The Bacillus [Bacterium] pneumonice is a 

 very pleomorphic organism occurring in sputum or in the 



blood of an inoculated animal 

 generally as a short rod sur- 

 rounded by a marked capsule. 

 It is non-motile, does not form 

 spores, and is readily stained 

 with the ordinary anilin dyes, 

 but is Gram-negative. In culti- 

 vations it forms short rods, long 

 rods, chains, and even filaments, 

 the capsule being absent, but 

 this is regained on passage 

 through a susceptible animal. 



Cultural characters. The B. 

 pneumonice is aerobic and facul- 

 tatively anaerobic, and may 

 produce indole. It grows readily 

 on the various culture media 

 from 20 to 37 C., on agar and 



FIG. 47. Friedlander's 

 pneumo - bacillus. Gelatin 

 stab - culture, seven days 

 old. 



blood-serum forming a copious, 

 viscid, greyish growth ; on gela- 

 tin, a thick, white, shining, 

 porcelain - like growth without 

 liquefaction ; and in stab-cultures in gelatin a so-called 

 nail-shaped growth is developed (Fig. 47), consisting of a 

 white growth along the needle-track, tapering from above 

 downwards, and at the surface heaped up and expanded, 

 forming the " head " of the nail, gas-bubbles frequently 

 forming. On potato a copious whitish growth develops. 



