284 PYOGENIC BACTERIA. 



culating fluid, and in man, as in animals infected experimentally, a 

 microscopic examination of the blood for microorganisms usually 

 gives a negative result. Culture experiments may, however, demon- 

 strate their presence. Thus recent investigations by Netter, Eisel- 

 berg, and others show that the pus cocci are usually present in the 

 blood in small numbers, as demonstrated by culture experiments, in 

 septic infection from wounds. 



2. STAPHYLOCOCCUS PYOGENES ALBUS. 



Isolated by Rosenbach (1884) from the pus of acute abscesses, in 

 which it is sometimes the only microorganism present, and some- 

 times associated with other pus cocci. In thirty-three acute abscesses 

 examined by Passet (1885) it was associated with Staphylococcus 

 aureus in eleven, with Staphylococcus citreus in two, with Strepto- 

 coccus pyogenes in one, with both Staphylococcus citreus and Strep- 

 tococcus pyogenes in one, and was obtained alone from four. 



In its morphology this micrococcus is identical with the preced- 

 ing, but it is distinguished from it by the absence of pigment and 

 by being somewhat less pathogenic. Surface cultures upon nutrient 

 agar or potato have a milk-white color. It liquefies gelatin in the 

 same way as does the golden Staphylococcus, but the deposit at the 

 bottom of the liquefied gelatin is without color. In the temperature 

 conditions favorable to its growth, and in its biological characters 

 generally, with the exceptions noted, it is not to be distinguished 

 from the species previously described. According to Fliigge, it is 

 more common than aureus among many of the lower animals. 



Pathogenesis. Fortunati has tested the comparative pathogenic 

 power of Staphylococcus aureus and Staphylococcus albus by inocu- 

 lations into the cornea of rabbits. A purulent infiltration of the 

 cornea and panophthalmitis resulted when Staphylococcus aureus 

 was inoculated upon the surface of the cornea by scratching with an 

 infected needle, but inoculations made in the same way with Staphy- 

 lococcus albus healed spontaneously or gave rise to a perforating 

 ulcer. After paracentesis of the cornea with an instrument infected 

 with Staphylococcus aureus panophthalmitis developed in thirty hours; 

 the same result occurred at the end of sixty to seventy-two hours 

 when the instrument was infected with Staphylococcus albus. When 

 a sterilized instrument was used the result was negative. In bacteri- 

 ological researches made by Gallenga, in cases of panophthalmitis in 

 man, Staphylococcus albus was found in ten cultures and Staphy- 

 lococcus aureus in nine. 



Staphylococcus Epidermidis Albus (Welch). 

 The recently published researches of Welch show that a white 

 Btaphylococcus, probably identical with Staphylococcus pyogenes 



