308 PUBLIC HEALTH BACTERIOLOGY 



before excision, not to manipulate it roughly, or bacteria 

 may enter the circulation) ; (2) Making cultures from 

 similar material, by successive strokes on agar tubes or 

 plates ; (3) Inoculation of the cultures into a guinea-pig 

 or mouse, subcutaneously. If anthrax bacilli are present 

 the animal usually dies within two days, and post 

 mortem the tissues around the site of inoculation show 

 intense inflammatory oedema, swelling, and gelatinous 

 change, with small haemorrhages. On microscopic exami- 

 nation, numerous bacilli are seen. The internal organs 

 show congestion and cloudy swelling, and sometimes 

 small haemorrhages, and their capillaries contain enor- 

 mous numbers of bacilli, so that they appear as if 

 injected with them. The spleen is notably enlarged 

 (especially in the ox dead of anthrax, being two to three 

 times its natural size, hence the name "splenic fever"), 

 is of a dark-red colour, and on section is soft and friable, 

 at times almost diffluent. Films from the pulp contain 

 enormous numbers of bacilli mixed with red cells and 

 leucocytes of the lymphocyte and large mononuclear 

 varieties. The lymphatic system is generally much 

 affected, the glands and vessels being swollen and containing 

 bacilli in very great numbers. The intestines are 

 enormously congested, the epithelium is more or less 

 desquamated, and the lumen filled with a bloody fluid. 

 (Muir and Ritchie.) 



2. Methylene-blue Reaction. Depends on the disintegra- 

 tion of the capsules of the bacilli, which occurs when these 

 are imperfectly fixed. It serves for the easy recognition 

 of anthrax bacilli in blood and other bodily fluids, where 

 putrefactive and other bacilli are present. Dry a loopful 

 of blood on a slide ; hold it for one second in the flame ; 

 repeat three times. Stain for a few seconds in old solution 

 of methylene-blue, wash in water, and dry. Examine dry 

 and without a cover-glass, when between and near the 

 bacteria, violet or reddish-purple tinted granular or 

 amorphous matter is seen. (M'Fadyean's test.) 



Capsules can be demonstrated in smear preparations 

 from organs, by staining in 2 per cent watery solution of 

 methylene- violet (heating). Wash in water for 2 seconds. 

 Wash in 1 per cent acetic for 6 to 10 seconds. Wash in 



