546 



PATHOGENIC MICROORGANISMS 



feld.i The condition which these microorganisms characteristically 

 produce is a catarrhal conjunctivitis which usually attacks both eyes. 

 The inflammation is especially noticeable in the angles of the eye, most 

 severe at or about the caruncle. There is rarely much swelling of the 

 conjunctiva and hardly ever ulceration. The condition runs a subacute 

 or chronic course. Its diagnosis is easily made by smear preparations 

 of the pus which is formed with especial abundance during the night. 



Morphology. — In smear preparations from the pus, the microorgan- 

 isms appear as short, thick baciUi, usually in the form of two placed 

 end to end, but not infrequently singly or in short chains. Their ends 





Fig. 117. — Mokax-Axenfbld Diplo-Bacillus. 



are distinctly rounded, their centers slightly bulging, giving the bacillus 

 an ovoid form. They are usually about two micra in length. 



They are easily stained by the usual anihn dyes, and, stained by 

 the method of Gram, are completely decolorized. 



Cultivation. — The Morax-Axenfeld bacillus can be cultivated only 

 upon alkaline media containing blood or blood serum. 



It grows poorly, or not at all, at room temperature. 



Upon Loeffler's blood serum, colonies appear after twenty-four to 

 thirty-six hours as small indentations which indicate a liquefaction of 

 the medium. Axenfeld states that eventually the entire medium may 



<■ Axenfeld, Cent, f . Bakt., xxi, 1897. 



