166 



BACTEKIOLOGY OF THE EYE 



are then found. It can best be recultivated when the fluid mass is 

 poured out into ascites bouillon. An eight-day culture can no longer 

 be propagated. These statements are generally agreed to, but ex- 

 ceptions do occur. MacNab made elaborate resistance tests in my 

 laboratory, comparing the Morax-Axenfeld Diplobacillns with the 

 Diplobacillus liqnefacicns (Petit). He found that the Diplobacilkw 

 liquefaciens could be propagated from a sixty-days-old blood- serum 

 culture. A strain of the Morax-Axenfeld Diplobacillus was similar. In 



FIG. 24. TWENTY-FOUR-HOUR CULTURE ON SERUM AGAR. 



the water- bath both forms were killed when kept for five minutes at 

 55 C. ; at 50 C. a growth still occurred. 



When sterile splinters of wood were infected with Diplobacilli from 

 an agar or serum-agar culture, and then dried in the oven for four 

 days, media could still be inoculated with them ; this was the case with 

 both types of organism. From this I consider that the Diplobacilli 

 could, under certain circumstances, remain a long time alive outside 

 the body, and perhaps still cause infection. This is probably more 

 often true for dried secretions than for dried cultures, as is" the case 



