MALLEIN. 323 



not to stain for too long a time or to decolorize with 

 alcohol loo energetically. 



No yiiethod of contrast-stain for this organism in 

 tissue has been devised. 



In properly stained tissues the bacilli will be found 

 most numerous in the centre of the nodules, becoming 

 fewer as we approach the periphery. They usually lie 

 between the cells, but at times may be seen almost iill- 

 ing some of the epithelial cells, of which the nodule 

 contains more or less. They are always present in these 

 nodules in the tissues; they are rarely present in the 

 blood, and, if so, in only small numbers. 



Diagnosis of the Disease by the Method op 

 Steauss. — From what has been said the diagnosis of 

 glanders by routine bacteriological methods is certain 

 and relatively easy, but requires time. In clinical work 

 it is of great importance for the diagnosis to be estab- 

 lished as quickly as possible. With this in view Strauss 

 devised a method that has given entirely satisfactory 

 results. It consists in introducing into the peritoneal 

 cavity of a male guinea-pig a bit of the suspected tissue 

 or culture. If it be from a genuine case of glanders, 

 the testicles begin to swell in about thirty hours, and 

 as this proceeds the skin over them becomes red and 

 shining, desquamation occurs, evidences of pus-forma- 

 tion are seen, and, indeed, the abscess (purulent orchitis) 

 often breaks through the skin. The diagnostic sign is 

 the tumefaction of the testicles. 



Mallein. — The filtered products of growth of the 

 glanders bacillus in fluid media represent what is known 

 as mallein — a group of compounds that bear to glanders 

 pretty much the same relation that tuberculin bears to 

 tuberculosis. It is used with considerable success as a 



