, BACILLUS ERYTHROSPORUS 337 



Black lorula {Saccharoviyces niger). — This yeast is 

 frequently met with in the air. Cultural characters : 



Gelatine Plates and Tubes. — Forms a heaped-up black 

 mass. 



Potatoes and Bread. — Grows as a sooty black crust, with 

 a dry furrowed surface. 



Bacillus Erythrosporus. — This organism, which occurs in 

 water, etc., is a slender bacillus, which may form chains, 

 and is very motile. From two to eight oval spores appear 

 at the ordinary temperature in each rod, which may extend 

 beyond the walls of the bacillus. They are characterised 

 by their reddish colour ; even when the bacillus is stained 

 with methylene-blue, the spores retain their reddish colour. 

 Cultural characters : 



Gelatine Plates. — Whitish colonies are formed, which 

 gradually spread over the surface ; around them in the 

 gelatine a peculiar fluorescence appears. The centres of the 

 colonies are usually brownish, the outer zones are light 

 yellowish-green. The colonies show radiate markings. 



Gelatine Tubes. — Grows abundantly both on the surface 

 and in the depth, and the whole tube assumes a green 

 fluorescent colour. The gelatine is not liquefied. 



Potatoes. — Produces a somewhat restricted growth, which 

 is at first reddish, but later becomes nut-brown in colour. 



Spirillum Finkler-Prior. — This organism was isolated by 

 Finkler and Prior in 1884, from the stools of persons 

 suffering from cholera nostras. Microscopically, it is very 

 similar to the spirillum of Koch, but is distinguished from 

 it by its ability to grow on potato at room-temperature, 

 while cholera will only grow at blood-heat. It does not 

 produce the indol reaction in so short a time as the cholera 

 spirillum. Cultural characters : 



Gelatine Plates. — Grows very rapidly in the form of 



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