STREPTOCOCCUS MUCOSUS 351 



Morphologically, though showing a marked tendency to form chains, on 

 solid media it often appears in the diplococcus form. It is enclosed in 

 an extensive capsule, which appears with much regularity and persist- 

 ence. Though very similar in appearance, therefore, to pneumococci, 

 these bacteria do not appear in the typical lancet shape. Upon solid 

 media they show a tendency to grow in transparent moist masses. The 

 regularity with which this microorganism ferments inulin medium, and 

 its agglutinative characters, make it probable that it is more accurate to 

 place it with the group of pneumococci than with that of streptococci.^ 

 (For agglutinations see section on pneumococcus agglutination, p. 364.) 



STREPTOCOCCI AND RHEUMATISM 



In 1910 Poynton and Paine "^ described a diplococcus which they 

 obtained from eight cases of acute rheumatic fever and with which 

 they were able to produce lesions in rabbits which they considered 

 typical of rheumatism. The organism was recovered from the blood, 

 the pericardial fluid, or the tonsil of their patients. They described a 

 minute Gram-negative diplococcus growing best in acid media and 

 under anaerobic conditions, but capable of growth on the surface of ordi- 

 nary media. Many investigators have attempted to confirm their work, 

 but with negative results for the most part, though some have found 

 streptococci and diplococci from rheumatic lesions. Recently Rosenow ^ 

 has reported the isolation of a streptococcus from the joints of seven 

 cases of articular rheumatism. He was also able to produce non- 

 suppurative arthritis, endocarditis, and pericarditis in rabbits with 

 these cultures. He describes them as intermediate in character between 

 the streptococcus viridans and streptococcus hemolyticus. 



More recently Rosenow ^ has reported the production of gastric 

 ulcers in rabbits and dogs with streptococci of a certain grade of viru- 

 lence. He has also obtained streptococci from human peptic ulcers 

 which showed a remarkable " affinity " for the gastric mucous membranes 

 of experimental animals. 



• Bisi, Jour. Exp. Med., 1905; Buerger, Cent. f. Bakt., I, xli, 1906. 



' Poynton and Paine, Lancet, 1900, ii, 861, 932. 



' Rosenmo, Jour. A. M. A., 1913, Ix, 1223. 



" Rosenow, Jour. A. M. A., 1913, Ixi, 1947, 2007. 



