On Certain Bacteria from the Air of New York City. 379 



126. Bacillus sordidus n. sp. ? 



Occurrence. " jMicrococcus soi'didiis " from Knd's laboratory. 



MorphoJoyij. Short bacilli, .6-1X1-1-5,", singly or in pairs, rarely a short 

 chain ; not motile. In one preparation the bacilli were seen to be sur- 

 rounded by a transparent capsule. 



Biologfi. ]Milk coagulated, nitrate partly reduced, rosolic acid decolorized. 

 The agar growth is very viscous and that on lactose-litnuis geliitiii forms 

 a gTeat jelly-like mass which may collect to a huge extent in the bottom 

 of the tube. 



Remarls. I have seen no description of this species. 



Composition of the Media. 



The following formiilse will explain the composition of the 

 media used in the preceding investigations. All media were 

 rendered alkaline to litmus to such a degree that they were still 

 acid to phenol-ptalein, requiring from .1 to .2 cc. of tenth normal 

 sodium h3'drate * for every cubic centimeter of the medium to 

 render it neutral to the latter indicator. But if the medium, as 

 first prepared, turned out more alkaline than this, no acid was 

 added to it. The ordinary method of titration was used. 



Bkoth. Gelatin. 



Extract of meat (Liebig's), .. .5 gr. Broth as above prepared, with the 



Salt (XaCl), 5 gr. addition of 10 per cent, gelatin. 



Pepton 10 gr. 



Water ( filtered ) , 1000 cc. 



Two eggs ( to clear ) . 



Agar. Glycerine agar. 



Broth as above with 1 per cent, agar- Agar with 6 per cent, gijceriue. 

 agar. 



Lactose-litimus agar. 



Agar as above with 2 per cent, lactose and litmus enough to render dis- 

 tinctly purple. The litmus should Ije added as late as possible, as long boiling 

 with the medium injures the color. 



Fermentation broth. Milk. 



Pepton, 10 gr. Commercial milk, rendered alkaline 



Salt, 5 gr. if necessary. 



Glucose, 20 gr. 



Water, 1000 cc. 



* 4 grams of pure sodium hsihatc to 1 liter of distilled water. 



