Staphylococcus Pyogenes Aureus et Albus 289 



STAPHYLOCOCCI PYOGENES AUREUS ET ALBUS. 



Distribution. The cocci are not widely distributed in 

 nature, seeming not to find a purely saprophytic existence 

 satisfactory. They occur, however, upon man and the 

 lower animals, and can occasionally be found in the dusts of 

 houses and hospitals, especially in the surgical wards if 

 proper precautions are not exercised. They are common 

 upon the skin, in the nose, mouth, eyes, and ears of man; 

 they are nearly always present beneath the finger-nails, 

 and they sometimes occur in the feces, especially of chil- 

 dren. 



Fig. 89. Staphylococcus pyogenes aureus, from an agar-agar culture. 

 X 1000 (Gunther). 



Morphology. The cocci are small, measuring about 

 o. 7 p. in diameter. When properly stained, the organisms are 

 found to consist of hemispheres separated from one another 

 by a narrow interval, the approximated surfaces being flat- 

 tened. As observed in hastily stained preparations, they 

 are spheric. There is no definite grouping in either liquid 

 or solid cultures. It is only in pus or in the organs or tissues 

 of diseased animals that one can say that a true staphylo- 

 coccus grouping occurs. 



The organisms are not motile and have no flagella. 



Staining. The organisms stain easily and brilliantly 

 with aqueous solutions of the anilin dyes and by Gram's 

 method. 



