2i6 MICRO-ORGANISMS AND DISEASE [chap. 



specimens and in culture. Tlie morpliological and cultural 

 characters of the microbe are shown in F'igs. 72 and 73. 



The microbe when examined from a cultivation is often 

 rod-shaped — more often than in the tissue of tlie grouse. 

 The motile forms are common in recent cultivations ; in 

 cultivations some days old most of the microbes are non- 



FiG. 73.— FiL^i Specimen of Blood of Grouse in Grolse PIisease, showing 

 THE Nuclei of Red Blood Discs and a Nu."\icer of the Uacjlli. 



motile. Cultures inoculated into mice and guinea-pio-s 

 produce general infection, and rapidly death, mice being 

 more susceptible than guinea-pigs ; in both animals the 

 disease produced is a double-sided pneumonia. Sparrows 

 are also susceptible, but less so than the common bunting 

 and yellow-ammer, which animals are highly susceptible ; 

 also in these the disease produced is a double-sided pneu- 

 monia. The microbe is present in numbers in the heart's 

 blood, but jjarticularly in the diseased lung. 



