DISEASES OF THE OX AND SHEEP. 245 



beneath the mucous membrane of the digestive tube. The lungs 

 are turgid with blood, and the heart is marked both externally 

 and internally with dark purple spots and filled with dark and 

 partly coagulated blood. As in black quarter, extravasations 

 of blood are to be seen, and these are probably caused by sudden 

 congestions, attended by rupture of the vessels and consequent 

 effusion. Sometimes a sheep may live for several days ; but as 

 a rule the animal is actually dead within a couple of hours from 

 the time when it was in the enjoyment of good health. This 

 suddenness seems to be due to a general clotting of the blood 

 within the smaller vessels of the tissues. 



Now we proceed to give a short description of the germs 

 which cause anthrax fever. We propose to follow the admirable 





Fig. 28. — Fresh Specimen of Blood taken from the Heart of a Mouse 



WHICH HAS DIED OF AnTHRAX. 



1. Blood discs. 2. White blood- corpuscle. 3. Bacilli anthracis. 

 Magnifying power 700. After Klein. 



account of them given by our former tutor, Dr. Klein. In the 

 blood of any animal which has died of anthrax numbers of stiff 

 rods differing slightly in length are found. Koch succeeded in 

 cultivating these bacilli artificially, and showed that they multiply 

 by division, and grow so as to become long, homogeneous- 

 looking filaments, which are straight or twisted. If free access 

 of air is allowed, bright oval spores appear in them, and the 

 filaments become homogeneous and swollen. These spores then 

 become free, and, when artificially cultivated and injected into 

 an animal (rodent), they germinate into the characteristic bacilli. 

 These bacilli elongate and divide, and in artificial cultures again 

 grow into long filaments, which again form spores. The single 

 bacilli measure between 0*005 and 0'02 mm. in length, and 

 between 0*001 and 0*0012 mm. in breadth. 



