BACILLUS OF DUCREY 549 



before the pus has had a chance to cool off or to be exposed to Ught. 

 When buboes are not available, the primary lesion may be thoroughly 

 cleansed with sterile water or salt solution, and material scraped from 

 the bottom of the ulcer or from beneath its overhanging edges with a 

 stiff platinum loop. This material is then smeared over the surface of a 

 number of blood-agar plates. 



Upon such plates, isolated colonies appear, usually after forty-eight 

 hours. They are small, transparent, and gray, and have a rather firm, 

 finely granular consistency. The colonies rarely grow larger than pin- 

 head size, and have no tendency to coalesce. At room temperature, 

 the cultures die out rapidly. Kept in the incubator, however, they may 

 remain alive and virulent for a week or more. 



On the simpler media, glucose-agar, broth, or gelatin, cultivation 

 is never successful. On moist blood-agar and in the condensation 

 water of such tubes, the bacilli have a tendency to grow out in long 

 chains. Upon media which are very dry, they appear singly or in 

 short chains. 



Pathogenicity. — Besangon, Griffon, and Le Sourd, and others, have 

 succeeded in producing lesions in man by inoculation with pure cultures. 

 Inoculation of the lower animals has, so far, been entirely without result. 



MICROCOCCUS MELITENSIS (MALTA FEVER) 



{Bacillus melitensis) 



Malta fever is a disease occurring along the Mediterranean coast 

 and its islands. It has been recently found to occur also in South 

 America, South Africa, China, and in the West Indies. The disease 

 is not very unlike typhoid fever, though more irregular and with a 

 lower mortality. It is accompanied by joint pains, sweating, constipa- 

 tion, and occasionally orchitis. The spleen is almost always enlarged. 



Recent investigations into the manner in which this disease is con- 

 veyed have revealed that it is primarily an infection of goats. A large 

 percentage of the goats on Malta were shown to be infected and passed 

 the organism with the milk. Forty per cent of the goats gave positive 

 agglutination tests and the organisms have been found in the milk in 

 about 10 per cent of the animals. 



The most susceptible animals seem to be goats, but horses and cows 

 are also susceptible. In guinea-pigs and rabbits the disease can be ex- 

 perimentally produced, but usually takes a protracted course. Monkeys 



