145 MICRO-ORGANISMS AND DISEASE. [CHAP. 



0*02 mm. in length, and o.ooi to 0-0012 in thickness ; they 

 are truncated. 1 The spores produced by growing the bacilli 



1 IG. 79. PART OF A BLOOD CLOT FROM THE HEART OF A MOUSE DEAD OF 

 ANTHRAX. 



Magnifying power 500. (Stained with Spiller's purple.) 



with free access of air are about o'ooi mm. thick, and about 

 o'oo2 to 0.003 mm. long. They are not stained by the 

 ordinary dyes and differ herein from the bacilli. 



In the human subject malignant anthrax occurs as " woolsorter's 

 disease " ; for the aetiology and pathology of this malady see Spears 

 (Reports of the Medical Officer of the Local Government Board, 1881 and 

 1882) and Greenfield (ibid. 1881). It occurs also in sorters of hides. 



All rodents and herbivorous animals are susceptible to anthrax ; rats 

 are, however, infected with difficulty, pigs are very insusceptible, and 

 so are dogs and cats. Infection of animals can be produced by in- 

 oculation into the skin and subcutaneous tissue intravascular injections, 

 and by inhalation of spores (Buchner, Untersuchungen iiber niedere 

 Pilze, by Prof. v. Nageli, 1882, p. 178). In wools^rter's disease the 

 usual mode of infection is by inhalation of spores adhering to the wool 

 of the fleeces of animals (sheep, goats) dead of anthrax. As in rodents 

 infected with anthrax, so also in man, the blood-vessels of all organs 

 contain the bacilli, and extravasations of the infected blood are frequent 



1 It is generally assumed that the bacilli are the same ii all animals 

 affected with splenic fever, but this is most undoubtedly not the case, 

 as has been already pointed out by Huber (Deutsche med. Woch. 1881); 

 the bacilli of the guinea-pig are thicker than those of the mouse or 

 sheep, and these again are thicker than those of the rabbit. 



