GONOCOCCUS. MENINGOCOCCUS 179 



Cultivation. Cultivation has occurred on blood-agar, the 

 blood being added in the proportion of one to two. Colonies 

 are small, round globules. 



Staining. With borax, methylene-blue, decolorized with 

 weak acetic acid. 



Patho genesis. Probably a mixed infection occurs in most 



^^^^^^ 



Fig. 88. Smear of pus of chancroid of penis (X 1500) (Davis) (photo- 

 micrograph by Mr. L. S. Brown). 



chancroids, especially if buboes result. The bacillus of 

 Ducrey is not found in unopened buboes, though often con- 

 taminating the ulcerated ones. 



The disease has been reproduced by inoculation of the 

 human subject. Laboratory animals are immune. 



