66 BACTERIOLOGICAL DIAGNOSIS. 



assistance from a bacteriological examination in the 

 cutaneous form of the disease ; he may search for the 

 specific bacillus in the sputum in a supposed case of 

 wool- sorter's disease, but he must be careful in his 

 interpretation of his result, as bacilli which might be 

 mistaken by an untrained observer relying on the 

 morphological appearances alone, sometimes occur in 

 the sputum. The search for bacilli in the faeces in a 

 supposed case of intestinal anthrax must be relegated to 

 an expert. 



The true nature of a case which is examined post- 

 mortem can easily be determined bacteriologically ; the 

 cut surface of the liver or spleen should be rubbed upon 

 a clean slide, and the films treated secundum artem. 

 They will probably show the bacilli in large numbers. 

 Sections may also be cut, or portions of the organs 

 fixed in the manner to be described subsequently and 

 forwarded to a bacteriological laboratory. 



In the later stages of any infection with anthrax the 

 bacilli may be found in the blood. They may be 

 apparent on examination of stained films, or by cultural 

 methods similar to those used in the diagnosis of 

 malignant pustule. 



The anthrax bacillus varies considerably in length, 

 but is always a large organism and may be considerably 

 longer than the diameter of a red blood corpuscle. It 

 is much thicker than the bacilli which have been dealt 

 with hitherto, and it is invariably straight. The ends 

 of these bacilli are cut sharply at right angles to the 

 sides of the organism, and may be even somewhat 

 concave; this is a most characteristic feature. The 

 anthrax bacillus stains by Gram's method (Plate I., 



fig- 4)- 



In cultures the appearances are somewhat different. 



