I I 8 BACTERIOLOGY. 



a pure infection was obtained by the inoculation 

 of field-mice, which have an immunity from bacil- 

 lary septicaemia. 



Streptococcus bombycis, Bechamp, (Micro- 

 zyma bombycis). Oval cocci '.5 p in diam., singly, 

 in pairs, or chains. They occur in the contents 

 of the alimentary canal, and in the gastric juice of 

 silkworms suffering from " flacherie " (" Maladie de 

 morts b lanes" " flaccidezza" " schlaffsucht"}. 



Streptococcus vaccinae. Cocci, -5 ^ in 

 diam., singly, in pairs, and in long or short chains, 

 and colonies. They are found in the fresh lymph * 

 of human and cow-pox, and in the pustules of 

 true small-pox. They are regarded as the active 

 principle of vaccine lymph, since filtration deprives 

 the latter of its infectious element. f The lympha- 

 tics of the skin in the region of the pustule of both 

 human and sheep-pox are filled with cocci. Suc- 

 cessful vaccination has been stated to result from 

 artificial cultivations. J 



Streptococcus perniciosus (Parrot disease]. 

 Cocci* singly, in chains, and in zoogloea have 

 been described in connection with a disease of the 

 grey parrot (Psittacus erithacus). This disease 

 is fatal to about 80 per cent, of these parrots' 

 imported to Europe. They suffer from diarrhoea 



* Cohn, Vir chow's Archiv. 1872. 



t Chauveau, Comptes Rendus, 1868, and Burdon Sanderson, 

 Reports on the Intimate Pathology of Contagion. 

 \ Quist, St. Peter sburgh Med. Wochenschr. 1883. 

 Wolff, Virchawfs Archiv. 1883. 



