60 



PROTEUS VULGARIS. Hauser. 



INCLUDED IN THE BACTERIUM TERMO OF OLDER WRITERS. 



Origin. Very widely distributed. Is commonly 

 present in the putrefaction of animal proteids; has also 

 been met with in water, in meconium, in purulent ab- 

 scesses, and in blood and tissues of two cases of fatal 

 putrid infection of intestines. 



Form. Rods, of varying length, from short oval 

 forms to those which are 2 to 6 times as long as wide. It 

 is usually bent and grows in pairs; may also form twisted, 

 interwoven threads. Roundish involution forms are 

 common. 



Motility. Actively motile. Flagella very numerous 

 and lateral. 



Sporulation. Not observed, though cultures are re- 

 sistant 1o desiccation and retain vitality for many months. 



Anilin Dyes. Stain readily. 



Growth. Very rapid. 



Gelatin Plates. Rapid and extensive liquefaction of the gelatin. The 

 colonies are yellowish brown, with bristly borders, and in soft gelatin tend to 

 spread over the surface and assume peculiar figures. Detached portions of 

 colonies can be seen to move about "swarming islets." Disagreeable odor 

 and alkaline reaction. 



Stich Cultures. Rapid liquefaction along entire line of inoculation, so 

 that in a few days the entire contents are liquefied. The fluid is at first dif- 

 fusely cloudy, but later clears up and a flocculent sediment settles on the bot- 

 tom, while on ihe top a grayish white layer is formed. 



Streak Cultures. On agar, forms a grayish, slimy, rapidly spreading 

 growth. On potatoes, it forms a dirty colored, sticky covering. 



Oxygen requirements. Facultative anaerobe. 



Temperature. Optimum lies between 20 and 24. 

 Grows excellently in the incubator. 



Behavior to Gelatin. Rapidly liquefied. 



Aerogenesis. Forms hydrogen sulphide. 



Pathogenesis. Small doses have no effect. Injec- 

 tion of large quantities of cultures, or filtrates from these, 

 produces in rabbits and guinea-pigs toxic effects, and even 

 death may result. It is therefore toxicogenic, but not 

 pathogenic. 



NOTE. When surface colonies as those above present special character- 

 istic they can be reprinted on cover-glasses. To make such an impression or 

 "Klatsch" preparation, select a suitable spreading colony, wilh the aid of No 

 3 objective, then raise the lube of the microscope and carefully drop a clean- 

 cover-glass on top of the colony. Apply gentle pressure with a pair of forceps, 

 then grasp the edge of the cover-glass and carefully remove: allow to dry in 

 the air; fix and stain in the usual manner. 



In making the reprint only the growth should adhere to the cover-glass. 

 Considerable gelatin, solid or liquid, on the cover-glass, is undesirable and 

 interferes. 



