464 HEMOGLOBINOPHILIC BACILLI 
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 preparation 
under the microscope. 
2. r^to/rff/.— Material preferably obtained from an unopened bubo 
should be spread upon the surface of blood agar, employing the 
technique 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 trans- 
ferring material from one subject into another. Syphilis and chancroid 
may exist in the same patient. 
> The method of Teague and Diebert, using rabbit blood, is more rapid and quite as 
satisfactory. 
