PATHOGENIC SPIRILLA. 225 



cholera bacillus by the more energetic manner in 

 which they liquefy the gelatine. In this they resemble 

 more closely the Bacillus Finchleri. 



In South Russia, a bacterium, the Spirillum Met- 

 schnikaffii has been found in birds suffering from an 

 intestinal disease; this morphologically, and in its 

 behaviour in cultivations and towards staining re- 

 agents, so closely resembles the cholera bacillus that 

 they cannot be distinguished one from the other. It is 

 true that on gelatine plates a number of the colonies 

 may conduct themselves in an anomalous manner, 

 some looking very like Finckler's bacillus, whilst 

 others cannot be distinguished from the cholera bacil- 

 lus. But the only sure method of distinguishing the 

 Spirillum Metschnihoffii from the cholera bacillus is 

 by means of experiments upon animals. If, for ex- 

 ample, a small quantity of the former is introduced 

 with an inoculating needle into the breast muscle of a 

 dove, the bird dies after twenty-four hours at longest 

 of a specific disease, whereas it is almost completely 

 unsusceptible to an inoculation of the cholera bacillus. 

 An immense number of these spirilla are found in the 

 tissue fluid of the affected oedematous muscle, and 

 above all in the blood of the heart. 



Another spirillum, which is pathogenic in man, is 

 found in the blood of patients suffering from relapsing 

 fever, an illness which is generally restricted to 

 Eastern Europe and Asia, but which occasionally 



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