THE BIO LOO Y OF MICROBES, ETC. 131 



gelatine, giving rise to the characteristic but offen- 

 sive gangrenous odour. The same microbes have 

 been observed in various gangrenous tissues, and 

 also in the blood of patients suffering from ' Clou de 

 Biskra ' or ' Bouton d'Alep,' which excite gangrene 

 when injected into rabbits. 



Micrococcus perniciosus. According to Wolff 1 this 

 microbe is the cause of a disease of the grey parrot. 

 The cells measure 0*8 p in diameter, and occur 

 singly, in chains and zooglcea. They produce 

 nodules in the liver, lungs, spleen, and kidneys; 

 but inflammation around the nodules is entirely 

 absent. The microbes also occur in the blood. The 

 disease is said to be fatal to 80 per cent, of the 

 grey parrots imported into Europe. 



Micrococcus insectorum. This microbe occurs in 

 the digestive organs of the chinck-bug (Blissus 

 leucopterus) ; and is probably the cause of an infec- 

 tious disease of this insect. The cells are obtusely 

 oval (0'7 to 1 fj, long x 0'55 /JL broad), and occur 

 singly, in pairs, chains^ or zoogloea. They may be 

 cultivated in bouillon. 



Micrococcus of Tissue Necrosis in Mice. Dr. E. 

 Koch observed that a certain micrococcus, isolated 

 from putrid fluids, when injected into the ear of a 

 mouse, gave rise to tissue necrosis and death in 

 about three days. The microbe was not found in 

 the blood and internal organs. The cells measure 

 0'5 fi in diameter, and occur in chains and zoogloea. 



Micrococcus in whooping-cough. Whooping-cough 

 is undoubtedly an infectious disease, and, according 



1 Virchow'a Archiv, 1883. 



