420 MICRO-ORGANISMS IN WATER 



PEOTEUS VULGARIS 



LIQUEFIES GELATINE 



Authority. — Hauser, Xleher Fdulnis-Bakterien, Leipzig, 1885. 



WKere Found. — In putrefying animal substances. In water (Zimmermann). 

 Found also in sewage by Eoscoe and Lunt, ' Chemical Bacteriology of Sewage,' 

 Phil. Trans., vol. clxsxii., 1892, p. 644. Found also in urine in cases of cystitis 

 by Krogius (Helsingfors, 1892). The Proteus sidfureus found in water by 

 Holschewnikoff {Fortschritte der Medicin, vol. vii. p. 201) resembles the above, 

 and is probably identical with it. 



Microscopic Appearance. — Slightly bent bacilli, about 0*6 m broad, and of 

 very variable length up to 3'75 /j. ; also gives rise to snake-like threads, resembling 

 sometimes woven plaits of hair. Involution forms frequently occur. It is 

 very motile, and has long cilia. No spore formation has been observed. 



Cultures.— 



Gelatine Plates.- -The colonies are yellowish brown, with a bristly edge ; 

 from this margin spring processes consisting of coils of parallel bacilli, which 

 spread like tendrils into the surrounding gelatine, also giving rise to most 

 curious figures consisting of closely packed rows of bacilli, commonly called 

 ' wandering or swarming islets.' In the depth characteristically shaped zoogloea 

 forms are often met with. Eapid liquefaction ensues. 



Gelatine Tubes. — Liquefies the gelatine rapidly all along the needle's path ; 

 later, when all the contents are fluid, a whitish grey cloud is visible on the 

 surface, whilst an abundant deposit, consisting of thick, crumbly fragments, 

 collects at the bottom. 



Agar-agar. — Forms -a, thin, spreading, moist, shining, greyish white ex- 

 pansion. 



Potatoes.— Forms a dirty, smeary growth. 



Bemarks, — Pathogenic to rabbits and guinea-pigs. 



PROTEUS MffiABILIS 



LIQUEFIES GELATINE 



Authority. — Hauser, Ueber Fdulnis-Bakterien, Leipzig, 1885. 



Where Found.^In putrefying animal substances. In water (Zimraermann). 



Microscopic Appearance. — Bacilli about 0-6 /x broad and of variable length, 

 being sometimes almost round, and sometimes 2-0 to 3-7 m long. It gives rise to 

 involution forms more readily than the Proteus vulgaris, exhibiting spherical 

 or pyriform structures from 3*75 to 7'0 (jl in diameter. It is motile. No spore 

 formation observed. 



Cultures. — 



Gelatine Plates. — Forms a circular white expansion, which, under a low 

 power, appears brownish and finely granular ; the periphery is wavy and lobular, 

 from which extensions run out into the surrounding gelatine. There is less 

 movement to be seen in these liquefying expansions than in those formed by 

 the P. vulgaris, but they exhibit, like the latter, zooglcea forms. Liquefaction 

 is less rapid than in the case of, P. vulgaris. 



Gelatine Tubes. — Forms an expansion, surrounded by a liquid, circular 

 zone, filled with moving bacilli and threads. At the end of forty-eight hours 

 a thick, moist, and shining pellicle is formed, and in from two to three days 

 the whole contents of the tube are fluid. 



Remarks. — Pathogenic to rabbits and guinea-pigs. It is facultatively anaerobic. 

 No liquefaction takes place in the absence of oxygen. 



