68 BACTERIOLOGY FOR NURSES 



The staphylococcus aureus is found almost con- 

 stantly upon the skin, and is supposed to have at 

 times the power to penetrate the skin through the 

 sweat-ducts, several diseases of the skin being 

 attributed to its activities; while suppurative in- 

 flammations in all parts of the body are usually 

 found to contain the organisms. 



Infections from staphylococci are not unknown 

 among domestic animals ; horses, cattle, and rabbits 

 being more susceptible than other animals. 



The streptococcus pyogenes is a coccus slightly 

 larger than the staphylococcus, which grows in 

 chains of varying length, it being thought at one 



time that the length of the chain 

 t< 



..V / N /" signified the degree of virulence 



**' *". ' / of the germs, but this has not 



* '*"*' '. i 



been proven by experiment. 



FIG. 13. 



There are many so-called strains 

 of the streptococcus, and probably no other disease- 

 producing organism causes as many and varied 

 disturbances in man, being not only the primary 

 cause of many infections, but frequently found in 

 mixed and in secondary infections. Erysipelas, 

 puerperal fever, suppurative conditions of all of the 

 organs, pneumonia, ulcerative endocarditis (an 

 affection of the valves of the heart), otitis media (in- 



