DIPLOCOCCUS PNEUMONIA 369 



Pneumococci ferment inulin, if cultivated in inulin-serum-water 

 medium. Acid formation from the inulin results within two days 

 or more in coagulation of the serum and reddening of the litmus. 

 Streptococci because of their inability to attack the inulin leave the 

 medium unchanged.^ 



Cultivated on whole-blood-agar, streptococci usually cause hemo- 

 lysis, pneimiococci usually do not.^ In contradistinction to Streptococ- 

 cus viridans which does not hemolyze, pneumococci have a tendency on 

 these media to form the black, dry, paint-blister colonies.' 



Neufeld,* in 1900, noticed that normal rabbits' bile added in quan- 



spleen also contained these organisms. The capsule in all the preparations remained 

 uncolored, but the authors say that its existence was not to be doubted. Ascitic 

 broth inoculated from the peritoneal exudate of a rabbit dying from the infection 

 gave streptococci in extremely long chains and surrounded by capsules. These were 

 not so distinct as in the case of the organisms in the original smear preparations. 

 All fluid media (bouillon, milk, and ascitic broth) were said to be strongly acid after 

 twenty-four hours. These authors report that Achard and Marmorek have assured 

 them that they have seen capsulated streptococci, and that Marmorek showed them 

 some preparations in which one of his streptococci presented the same characters as 

 that isolated by them. 



Although Le Roy des Barres and Weinberg have used the term encapsulated, 

 they beheve that it would perhaps be more prudent to call their organism strepto- 

 coque aureole, since they were not able to define this capsule by staining it. 



Howard and Perkins {Howard and Perkins, Jour. Med. Res., 1901, iv, p. 163) 

 have lately described an organism, probably of the foregoing type, which was present 

 in a tubo-ovarian abscess and in the peritoneal exudate, the blood, and some of the 

 organs of a woman dying in the Lakeside Hospital, Cleveland, Ohio. The organisms 

 were biscuit-shaped cocci in pairs, usually arranged in chains of four, six, eight, 

 or twenty elements, and surrounded by a wide and sharply staining capsule. In the 

 artificial cultures special capsule stains, it was noted, failed to stain any definite area, 

 but numerous small deeply stained granules were to be seen within the halo, espe- 

 cially near its outer border. Howard and Perkins propose for the group composed of 

 the streptococci of Bonome, Binaghi, and their own organism, the name Strepto- 

 coccus mucosus. Streptococci isolated from cases of epidemic sore-throat have also 

 shown capsules (p. 343). 



Reference to the original descriptions of these various capsulated streptococci 

 will show that, with the exception of a rather poorly staining capsule, the majority of 

 these organisms are separated from the typical Streptococcus pyogenes or from the 

 pneumococcus by exceedingly shght and unstable morphological and cultural charac- 

 ters. The same is true of the difference observed in their pathogenic action in 

 animals. 



^Hiss, Cent. f. Bakt., xxxi, 1902; Jour. Exp. Med., vi, 1905. 



' SchollmiiUer, MUnch. med. Woch. 



' Hiss, Jour. Exp. Med., vii, 1905. 



* Neufeld, Zeit. f. Hyg., 1901. 

 24 



