THE STAPHYLOCOCCUS GROUP 267 



and it is a constant inhabitant of the intestinal flora of artificially fed 

 infants; it also occurs commonly, but in lesser numbers, in the intes- 

 tinal flora of the normal nursling. The organism has been repeatedly 

 isolated from the feces of adults, and it has also been isolated from the 

 intestinal tract of cattle. 1 



Pathogenesis. Man. Micrococcus ovalis is ordinarily a harmless 

 parasite of the intestinal tract; occasionally it becomes invasive 

 (usually secondarily) and produces various inflammations, according 

 to the tissues invaded and its association with other bacteria. Lewko- 

 wicz 2 isolated Micrococcus ovalis in nearly pure culture from three 

 cases of severe dysentery; the organisms were found to be capsulated 

 and resembled pneumococci in a striking manner. Jouhaud, 3 Thier- 

 celin, 4 Ramonovitsch, 5 and Gilbert and Lippman 6 have isolated the 

 organism either in pure culture or in association with other bacteria 

 from cases of cholecystitis, puerperal fever, appendicitis, various 

 intestinal inflammations, and even from the cerebrospinal canal in 

 cases of meningitis. The close resemblance of the organism to the 

 pneumococcus, which has been observed by Kruse, 7 Sittler 8 and others, 

 has doubtless led to confusion; many cases of "pneumococcus" infec- 

 tion of the stomach, gall-bladder, appendix and other intestinal adnexa 

 are probably infections with Micrococcus ovalis, and vice versa. 



Animal. Wilhelmi 9 has isolated Micrococcus ovalis from enteritides 

 of young cattle; Lewkowicz 10 has found the organism isolated directly 

 from human inflammations to be pathogenic for white mice. It exhibits 

 no pathogenicity as it occurs normally in the intestinal tract. 11 



Bacteriological Diagnosis. 1. Microscopical. The presence of con- 

 siderable numbers of diplococci in the feces with their approximated 

 ends slightly flattened, their distal ends somewhat pointed, staining 

 intensely with the Gram stain, is frequently sufficient evidence to 

 establish a tentative diagnosis of Micrococcus ovalis. 



2. Cultural. Various dilutions of feces or products of -inflammation 

 are plated either on dextrose agar or "streaked out" on blood agar. 



1 Wilhelmi, Landwirthschaft. Jahrb. f. Schweiz., 1899, xiii. 



2 Cent. f. Bakt., 1901, xxix, 635. 



3 These de Paris, 1903. 



4 Comp. rend. Soc. de biol., 1902, No. 27; 1908, Ixiv, 76. 



5 Ibid., 1911, Ixx, 122. 



6 Ibid., 1902, No. 30. 



7 Cent. f. Bakt., Orig., 1903, xxxiv, 737. 



8 Die wichtigsten Bakterientypen der Darmflora beim Sauglinge, u. s. w., Wurzburg, 

 1909. 



9 Landwirthschaftl. Jahrb. f. Schweiz., 1899, xiii. 



10 Loc. cit. 



11 Thiercelin, These de Paris, 1894; Compt. rend. Soc. de biol., April 15, 1899. Jou- 

 haud, These de Paris, 1903. 



