372 BACTERIA PATHOGENIC TO MAN 



of chronic urethritis varying in duration between four weeks to six years 

 or more, finding gonococci in 178 cases, the remainder giving negative 

 results. Neisser, out of 143 cases, varying in duration between two 

 months and eight years, found gonococci in 80 cases. 



BACTERIA RESEMBLING GONOCOCCI. 



Bumm described a number of micrococci which resembled gonococci 

 in form and staining. These assume importance largely because 

 they may be confused with the gonococcus. They occur on the con- 

 junctival and vaginal mucous membranes and cause confusion. One 

 of these micro-organisms, the micrococcus catarrhalis (see p. 365), has 

 an importance of its own. 



The Micrococcus Melitensis. 



This micro-organisrn was first discovered in a case of Malta fever by 

 Bruce in Malta in 1887. The disease is mostly confined to the shores 

 of the Mediterranean, but cases of it have been observed in Porto Rico 

 and the Philippines. The disease does not seem to be directly trans- 

 mitted from person to person. 



Morphology. Small rounded or slightly oval organism about 15/* in 

 diameter. It is usually single or in pairs, but in cultures short chains 

 are also met with. Durham has shown that in old cultures bacillary 

 forms occur. Gorham believes he has demonstrated that the coccus 

 has one to four flagella. 



Staining. It stains readily with the aniline dyes and is negative to 

 Gram. 



Cultivation. At 37 C. it grows on nutrient agar and in broth. The 

 colonies are not usually visible until the third day. They appear as 

 small round disks, slightly raised, with a yellowish tint in the centre. 



Methods of Diagnosis. During life the best means of diagnosis is by 

 the agglutination test. The serum from different persons agglutinates 

 in dilutions of from 1 : 10 to 1 : 1000. Cultures are readily obtained 

 from the spleen. 



The Ducrey Bacillus of Soft Chancre. 



This bacillus was first specifically described and obtained :n pure 

 culture by Ducrey in 1889. 



Morphology. About 1.5,u long and 0.4^ thick, growing often in 

 chains and in cultures, sometinies twisted together in dense masses. 



It stains best with carbol-fuchsin, and shows polar staining. 



Cultural Characteristics. The following method of cultivation has 

 given the best results. Two parts agar are liquefied at 50 C. and 

 mixed with one part human, dog, or rabbit blood. The blood from 

 the cut carotid of a rabbit may be allowed to run directly into the agar 



