

NON-PATHOGENIC BACTERIA. 91 



Several large spirilla and vibrio live in bog and rain-water, 

 but our space does not suffice to describe them. 



Micro-organisms found in Urine, When freshly passed, urine 

 of a normal state contains no bacteria. By contact with the air 

 and the urinary passages exposed to air, a great number of yeast 

 moulds and bacteria soon accumulate in the fluid. Bacteria 

 also enter urine through the blood and during its secretion. 



A number of bacteria have the property of converting urea 

 into carbonate of ammonia. 



The urine should be centrifuged and the deposit then exam- 

 ined. The drying and fixing must proceed very slowly, since 

 otherwise crystals of salts will be precipitated and mar the 

 specimen. 



Bacterium TJrese. 



Origin. Decomposed ammoniacal urine. 



Form. Thick, little rods, with round ends one-half as thick 

 as they are long. 



Properties. Does not dissolve gelatine ; changes urea into 

 carbonate of ammonia. 



Growth. At ordinary temperatures, very slowly. In two days 

 on gelatine very minute points, which in ten days have the size 

 of a cent. The colonies grow in concentric layers. 



Micrococcus TJreae. (Pasteur and Van Tiegham.) 



Origin. Decomposed urine and in the air. 



Form. Cocci, diplococci, and streptococci. 



Properties. Decomposes urea into carbonate of ammonia ; 

 does not liquefy gelatine. 



Growth. Grows rapidly, needing oxygen; can remain sta- 

 tionary below C. ; growing again, when a higher temperature 

 \s reached. 



Colonies on Plate. On the surface like a drop of wax. 



Stab Cultures. Looks like a very delicate thread along the 

 needle thrust. 



Other bacteria are found in urine in various pathologic pro- 

 cesses, such as tubercle bacilli, typhoid bacilli, gonococci, and 

 other pyogenic organisms. 



The Urobacillus liqnefaciens, found by Schnitzler and Kro- 

 gius in cystitis, is supposed to stand in close relationship to this 

 disease. 



