260 Wound Infection ; Suppuration 



Virulence. Experiments have shown that both Staphy- 

 lococci aureus and albus exist in attenuated and virulent 

 forms, and there is every reason to believe that in the major- 

 ity of instances they inhabit the surface of the body in a 

 feebly virulent condition. 



Serum Therapy. The treatment of streptococcus in- 

 fections with immune serum has not met with encouraging 

 success. Viquerat * has experimented in this direction and 

 found that goats are best adapted to the manufacture of 

 the serum ; but the literature of medicine contains very little 

 mention of ' ' antistaphylococcus serum" and of beneficial 

 results following its employment. 



STAPHYLOCOCCUS CITREUS (PASSET). 



An organism identical in many respects with the preceding, 

 except that its growth on agar-agar and potato is of a bril- 

 liant lemon-yellow color, and its pathogenicity for animals 

 doubtful, is Staphylococcus citreus of Passet.f As it is not 

 common, and is doubtfully pathogenic, it is of much less 

 importance than the previously described organisms. 



STREPTOCOCCUS PYOGENES (ROSENBACH). 



General Characteristics. The streptococcus is a non-motile, non- 

 flagellate, non-sporogenous, non-liquefying, aerobic and optionally anae- 

 robic, spheric organism, infectious for man and the lower animals, whose 

 division in one direction of space leads to its association in the form 

 of chains or "strings of beads." It stains by ordinary methods and 

 by Gram's method. 



Streptococcus pyogenes(Fig. 76) was found by RosenbachJ 

 in 1 8 of 33 cases of suppurative lesions, fifteen times by itself 

 and five times in association with Staphylococcus aureus. 



Morphology. The organisms are spheric, of variable size 

 (0.4-1 fJ. in diameter), and are constantly associated in pairs 

 or in chains of from four to twenty or more individuals. 

 Special varieties, known as Streptococcus longus (chains of 

 more than one hundred members) and Streptococcus brevis 



* " Zeitschrift fur Hygiene," xvm, 1894, p. 483. 



f " Untersuchungen iiber die Aetiologie der eitrigen Phlegmone 

 des Menschen," Berlin, 1885, p. 9. 



J " Mikroorganismen bei Wundinfektionskrankheiten des Menschen," 

 1884, p. 22. 



