STRKPTOGOCCUS PYOGENES. 141 



(a) In bouillon form short, slightly tortuous chains; 

 bouillon cloudy; gelatin is very slightly liquefied; signifi- 

 cant growth upon potato; growth even at 10° to 12°. 

 Virulence usually absent. Strept. brevis v. Lingels- 

 heim. 



(6) In bouillon the streptococci form very tortuous, 

 long chains (forty and more members), which malie up a 

 flocculent or slimy sediment, leaving the bouillon clear. 

 Gelatin always remains solid; visible growth on potato is 

 absent, virulence is usually great. No growth below 14° 

 to 16°. Strept. longus v. Lingelsheim. 



The subdivision of the Strept. longus into the following varieties 

 (Behring) has now only a historical interest, since according to 

 I3ehring's pupU, Knorr, the characteristics of these subvarieties, upon 

 repeated cultures, are variable, and so the identity of these subvarieties 

 can be demonstrated : (1) Turbidus, with turbid bouillon culture; 



(2) viscosus, with clear bouillon culture and delicate sediment; 



(3) conglomeratus, with clear bouillon and granular sediment. 

 The same was also found by Kruse and Pasquale (Ziegler's Beitrage, 

 XII, 1893, 433). Interesting but unsatisfactory is also Pasquale's at- 

 tempt at a classification of streptococci ( C. B. x v, 761 ) . Also Babes 

 came to little sharp differentiation ; for him, as for us, all forms (in- 

 cluding the Strept. lanceolatus) are connected by transition forms. 



The findings of Waldvogel are interesting. Three times he ob- 

 tained, after inoculation with Strept. longus (the bouillon remained 

 clear and there was an insignificant granular sediment), from the heart's 

 blood of the inoculated mouse an organism forming chains with from 

 four to six members, and causing a diffuse cloudiness of bouillon. 

 Upon potato both forms grew equally poorly. By growth in strongly 

 alkaline bouillon the long chain form could be transformed into one 

 producing a sli T;ht diffuse cloudiness; and by growth in almost neutral 

 bouillon of the form producing turbidity a race was again obtained 

 which produced no flocculi in clear fluid and formed long chains. 



After such experiences more recent authors do not make 

 a division of the Strept. pyogenes into difl:erent forms, and 

 prefer to designate the forms described by them as Strept. 

 pyogenes, the form being described in a few words. We 

 also believe this to be right. Compare also Zenoni, C. B. 

 XXI, 10, and the interesting studies of Seitz concerning 



gelatin liquefaction, and a Strept. longus with slight liquefaction; 

 also occasionally a Strept. longus with a visible and a Strept. brevis 

 without a growth on potato. Marignac and d'Espine found Strept. 

 brevis which formed sediments in bouillon and did not cloud it. 

 Marbaix proved complete independence of the length of the chains 

 and pathogenic quality. 



