BACILLUS OF DUCREY 427 



(Macacus) by the injection of a blood agar culture obtained from a 

 bubo. This same culture also produced a chancroid when inoculated 

 into a man. Several successful inoculations in a man are recorded 

 which appear to establish satisfactorily the etiological relationship 

 of the bacillus of Ducrey to the lesion. 



Bacteriological Diagnosis. 1. Microscopical. If material be removed 

 carefully from the base of an ulcer and spread gently upon a glass 

 slide to prevent the breaking up of the characteristic arrangement of 

 the bacilli in long intertwined chains, a definite diagnosis may fre- 

 quently be made by direct observation of the Gram-stained prepara- 

 tion under the microscope. 



2. Cultural. Material preferably obtained from an unopened bubo 

 should be spread upon the surface of blood agar, employing the technic 

 outlined above. As much material as possible should be inoculated 

 to insure growth of the bacilli. 



3. Inoculation of Patient. The forearm of the patient is thoroughly 

 cleaned, then scarified with a platinum needle infected with material 

 from the ulcer or from a pure culture. The lesion appears within 

 twenty-four hours and it is typically developed in from three to five 

 days. It is obvious that little or no immunity is produced, because 

 autoinoculation results in infection. The possibility of syphilis 

 must be borne in mind in inoculation experiments, particularly in 

 transferring material from one subject into another. Syphilis and 

 chancroid may exist in the same patient. 



