GLANDERS 191 



growth on the latter does not produce the characteristic 

 appearances seen when the organism is grown on potato. 



On potato the growth is apparent in three to four days ; 

 at first it has the appearance of honey, but later on becomes 

 yellower, and eventually darker, till it approaches a choco- 

 late colour. 



With the exception of the pyogenic organisms, glanders 

 is almost the only coloured pathogenic organism. Cultures 

 on all media rapidly become attenuated, and die easily 

 unless kept at blood-heat. Schenk states ' that the infective 

 power of the virus ' (probably meaning the specific dis- 

 charge) is not destroyed by drying for three months. This 

 is explainable if the organisms are protected by being sur- 

 roujided by a dried coating of albuminous matter. 



By some observers it is believed that the organism forms 

 spores, but no method of staining has yet been published 

 by which they can be demonstrated. 



Wethod of Staining. — The glanders bacillus stains with 

 difficulty with the ordinary aniline dyes, Loffler's methylene 

 blue being the best. The bacillus will not stain with Gram's 

 stain. When it is desired to stain it in sections, the follow- 

 ing procedure may be adopted : 



1. Wash the section in water. 



2. Stain in carbol-fuschine for tiventy minutes, heated to 

 50° (7. 



3. Transfer to slide ; blot tvith filter-paper ; heat with 1 per 

 cent, acetic acid for thirty seconds to one minute ; wash with 

 water ; blot ; dehydrate with alcQhol ; blot and mount in 

 balsam. 



Pathogenesis. — The disease is communicable to many 

 horses, mules, asses, field-mice, and guinea-pigs. Cattle 

 are entirely immune, and white mice and rabbits partly so. 



In man, glanders occurs after infection from a diseased 

 horse, generally through the infective discharge coming 



