PATHOGENIC BACTERIA. '363 



whether or not it forms spores. It stains by the Gram and the 

 Weigert fibrin method but requires to be stained for a longer 

 time than most Gram positive bacteria, and it is also colored 

 by the methods used for staining the tubercle bacillus. It 

 takes the dye, however, more readily than the tubercle bacillus. 

 In stained preparations it appears very similar to the tu- 

 bercle bacillus, and resembles it in having alternate colored 

 and unstained spots. Babes mentions short branching forms 

 with inverted pear-shaped extremities. Although several ob- 

 servers have reported success in attempts to cultivate the 

 bacillus of leprosy, their claims have been disputed. Organ- 

 isms resembling the diphtheria bacillus, two different kinds 

 have been cultivated on artificial media by Babes* and others, 

 but Babes regards these as merely adventitious. 



The leprosy bacilli lie for the most part deep in the skin, but 

 Babes also found them in the hair-follicles. He also found 

 them in the sputum, nasal secretion, in the conjunctival sac, 

 in the sperma, urethral secretion and elsewhere, but not in 

 the urine; only in small numbers in the mucous membrane 

 of the bladder, twice in the milk, once in the feces, in small 

 numbers in the pleura and peritoneal fluid. They are usually 

 absent from the blood, found only once in 12 cases. Often 

 in the vaginal secretion in those affected. They are very 

 abundant in the ulcers. 



The results of inoculation into man and the lower animals 

 of material coming from cases of leprosy have been uncertain. 

 The bacillus of leprosy has been found so constantly in the 

 tissues of those having the disease that it is generally admitted 

 to be the specific cause. The skin and the peripheral nerves 

 are the parts most affected, although other tissues and the 

 internal viscera may be involved. A granulation tissue, 

 forming nodules and thickenings, appears in the affected parts. 

 The bacilli are found in large numbers in the nodules, partly 



*Kolle and Wassermann. Erganzungsband. 1906. p. 160, 



