I 4 4 AIDS TO BACTERIOLOGY 



sporing, and is aerobic and facultatively anaerobic. It 

 is Gram-negative. 



Cultural Characters. The pneumo- bacillus grows well 

 on all the ordinary media, both at room-temperature and 

 at blood-heat, but loses its capsule under cultivation. On 

 agar and blood-serum it forms abundant moist, thick, 

 cream-coloured growths. On surface gelatin it forms a 

 whitish spreading layer, and in stab gelatin a nail-shaped 

 growth the growth being heaped upon the surface like 

 the head of a nail, and tapering from above downwards in 

 the line of the puncture; the gelatin is not liquefied. On 

 potato a well-marked white sticky layer develops. Milk 

 is usually slowly coagulated. There is an abundant 

 growth in broth, with a considerable deposit. It ferments 

 glucose, saccharose, mannite, and lactose energetically, 

 with the formation of gas and acid. Variations in its 

 power of fermenting occur. 



It is sometimes met with in the sputum, particularly 

 in bronchitis, and occasionally in association with the 

 Diplococcus pneumonia?. It is also found in stomatitis 

 and rhinitis, ulceration of the cornea, affections of the 

 throat (sometimes with a false membrane), and in broncho- 

 pneumonia. 



Mice are susceptible to infection, the guinea-pig is less 

 so, and rabbits are infected with difficulty. 



Other Pneumonic Conditions. 



There are also pneumonic conditions frequently com- 

 plicating other diseases, and most frequently seen in 

 young children in the course of measles and whooping- 

 cough, in influenza, in typhoid fever, in plague, and 

 after operations about the mouth and throat (' septic ' 

 pneumonia). Although acute croupous pneumonia may 

 complicate these diseases, the pneumonic process is usually 

 of a different type, starting in a number of scattered 

 patches, which, however, may coalesce and so involve 

 large areas. 



Micrococcus Melitensis. 



The causative agent of Malta or Mediterranean fever is 

 the M. melitensis, a small coccus occurring singly, in 

 pairs, or in short chains, with an active Brownian move- 

 ment. (It is doubtful if it is a true motility, though 



