170 



BACTERIOLOGY OF THE EYE 



pagated from bouillon on to ordinary agar. The Petit type certainly 

 lost its power of liquefying gelatine, but it could always be grown on 

 simple media, and in any generation could be grown in bouillon, and 

 from there again back on agar, which transference never was possible 

 with the Morax-Axenfeld bacillus. 



(In these experiments the Petit JUplobacillux was cultivated for two 

 years on blood-serum.) 



The Morax-Axenfeld Diplobacilliis, too, can sometimes produce the 

 same form of hypopyon-keratitis. This Petit had not had the oppor- 

 tunity of observing when he recorded his type. In my own material 



FlG. 28. DlPLOBACILLE MORAX-AXENFELD. 



Colonies ' Mammelonnees ' (PETIT). 

 Also occurs in Petit's type. 



FIG. 29. GELATINE STAB CUL- 

 TURE OF PETIT'S BACILLUS. 



Funnel-shaped excavation at 15 C. 



consisting of twenty-three cases of diplobacillary keratitis, according to 

 the analysis of Dr. Agricola, one-third were caused by the Morax- 

 Axenfeld type, and an even higher proportion is recorded by Paul and 

 byErdmann. These two writers consider that the two types probably 

 are identical. I am of the opinion that they are very closely related, 

 but that they must be looked upon as variations of the same family 

 so long as a complete transference of the one type into the other 

 be accomplished. It may, perhaps, be possible. This point of view 

 cannot is taken by Zur Nedden, who only found the Petit type in 

 hypopyon-keratitis. It is very peculiar that the Petit variety is rare 

 in conjunctivitis, but is fairly frequently found in the cornea in 



