BACTERIOLOGY. 189 



diameter of the smaller ones) and whiter and more opaque in 

 character. The organism grows more slowly when first trans- 

 planted from the animal body to agar than in subsequent trans- 

 plantations on agar. Microscopically, the colonies exhibit a 

 lighter peripheral band and a thicker, raised, slightly granular 

 center which, when examined by direct light, gives a considerably 

 darker appearance than the periphery. 



In gelatin, somewhat similar, though slightly more delicate, 

 colonies to those on agar are formed. In stab-cultures the gelatin 

 is not liquefied. It was pointed out by some observers at the 

 Conference that some of the freshly-isolated pneumonic cultures 

 caused no turbidity when grown in bouillon, the growth rapidly 

 falling to the bottom of the media and leaving the supernatant 

 fluid clear. However, this is not invariably the case, as other 

 pneumonic cultures cause slight turbidity. These variations in 

 the different cultures evidently depended more upon the amount 

 and manner of inoculation of the organisms and the character of 

 the media than upon any particular characteristic of the culture 

 itself. 



In Manila, we have, since the Conference, studied three differ- 

 ent bubonic cultures recently isolated — one from Shanghai, one 

 from Hongkong, and one from Mariveles, Philippine Islands — 

 and three cultures from different pneumonic cases. These were 

 each inoculated in tubes of bouillon and grown side by side at 

 room temperature. No difference in growth as to the cloudiness 

 of the bouillon, amount of sediment, etc., could be observed in 

 the different tubes. In one of the pneumonic cultures and in one 

 of the bubonic ones the growth and flocculi seemed somewhat 

 heavier than in the other tubes. The growth in all of the cultures 

 became visible, about the second day, in the form of fine flocculent 

 masses which later greatly increased in size and became depos- 

 ited partly along the sides and at the bottom of the tubes. The 

 bouillon in all was slightly clouded. Microscopical specimens 

 from the different cultures revealed chains of coccoid bacilli. 



MUCUS PRODUCTION. 



The production of mucus by the pneumonic strain when grown 

 upon agar slants has been marked, but varies gi'eatly, as is also 

 the case with bubonic strains, according to the temperature at 

 which the cultures develop. Grown at ice-box temperature, the 

 culture forms a crumbly mass when collected upon the platinum 

 loop and, when this mass is placed in saline solution, it is ex- 



