92 MICRO-ORGANISMS AND DISEASE. [CHAP. 



which was characterised by the following appearances : The 

 blood of all the organs contained very numerous bacteria, the 

 spleen and lymphatic glands were enlarged, and the lungs con- 

 gested ; but there were no extravasations and no peritonitis. 

 The smallest quantity of this blood inoculated into the skin 

 or cornea of another rabbit produced after an incubation of 

 ten to twelve hours distinct rise of temperature, and death 

 after sixteen to twenty hours. The conditions after death 

 were the same as above. Everywhere the blood contained 

 the bacteria. They are rods somewhat pointed at both ends, 

 measuring about 0-0014 mm. in length and 0*0006 mm. in 

 breadth. When stained, they show at each end a deeply- 

 tinted granule, the middle part remaining unstained ; for this 



FIG. 38. BLOOD OF PIGEON, DEAD OF SEPTICAEMIA. 

 Four blood-discs and four bacteria-termo are shown. 



reason they are easily mistaken for a diplococcus. Generally 

 these rods occur singly ; occasionally they form a chain of 

 two, or more than three. 



They have been cultivated successively in beef broth, blood 

 serum, gelatine, and a mixture of gelatine and broth and 

 peptone. The cultures have the same virulent properties as 

 the original blood. 



Mice, pigeons, fowls, and sparrows are also very susceptible 

 to these bacteria ; but guinea-pigs, dogs, and rats resist them 

 successfully. 



The microbe found by Pasteur in human saliva, which he 

 cultivated, and with which he produced septicaemia in 



