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A MANUAL OF BACTERIOLOGY 



the aureus, and are only occasionally found alone, being 

 usually associated with the aureus. Cheyne, however, 

 states that in his experience the albus is more virulent 

 than the aureus, and mixed infections with the aureus are 

 regarded as more severe than infection with the aureus 

 alone. The albus has been found in some cases of pan- 

 ophthalmitis, and is said by Fliigge to be commoner than 

 the aureus in the lower animals. 



Chief Types of Human Micrococci 



Andrewes and Gordon 1 regard the aureus, albus, and 

 citreus merely as variants of a single species, the Micro- 

 coccus pyogenes. They found that every variety of colour, 

 from orange, through yellow to white, might be obtained 

 by cultivation. The Micrococcus fiavescens, met with by 

 Babes in abscesses, may probably be placed in the same 

 category. On the other hand, the Micrococcus epidermidis 

 (albus), first described by Welch as occurring on the skin, 

 in stitch abscesses, etc., and feebly pathogenic compared 



1 Rep. Med. Off. Loc. Gov. Board for 1905-06, p. 543. 



