256 AGRICULTURAL BACTERIOLOGY 



the subacute type the duration of the disease is from one 

 to seven days. Tumors or carbuncles are quite common. 

 They usually appear on the shoulders and neck, and are 

 due to the bruising of the parts, which injury gives rise to 

 a collection of the bacilli within the blood-vessels of the 

 parts, inducing inflammation, followed by the development 

 of the tumor. Carbuncles may also be occasioned by in- 

 fection through a wound. 



The subacute type is the most common, and is the only 

 form that can be treated. It is also the type noted in most 

 isolated cases of anthrax. At the beginning of an outbreak 

 the first animals lost usually show few or no symptoms. 

 This rapid progress of the disease may be due to the lack 

 of resistance of the animal. Such rapid progress of the 

 disease often leads to suspicion of poisoning, or to death by 

 lightning. Such conclusions as to the cause of death may 

 lead to the careless disposal of the carcass, thus endangering 

 human life as well as causing a widespread outbreak, not 

 only on the farm but in the neighborhood. It is well to 

 consider all cases of sudden death in an animal, especially 

 when no definite cause can be given, as due to dangerous 

 causes, and to act accordingly in the handling and disposal 

 of the carcass. The slower process of the acute and sub- 

 acute types of anthrax and the evident symptoms give 

 greater opportunity for the recognition of the nature of the 

 trouble. The mortality from the disease is from 70 to 80 

 per cent. 



Lesions. The lesions are usually so characteristic that 

 they enable the recognition of the disease, or at least arouse 

 suspicion as to its probable cause. The most marked is 

 the dark blood, which may appear almost tar-like and which 

 does not coagulate as does normal blood. The spleen, or 

 milt, is usually greatly increased in size; it is dark red in 

 color instead of the grayish color of the normal organ. The 



