Upon the Pseudo- Diphtheria, etc. 33 



Axenfeld (41) notes certain differences between these 

 two groups of bacilli when grown on agar, bouillon and 

 blood serum. First, the so-called xerosis bacillus grows 

 sparingly on the agar, very slowly, sometimes showing 

 only after three or four days. It shows as small, very dry, 

 closely-adherent colonies ; while the Hofmann-Loffler pseu- 

 do-diphtheria bacillus grows more rapidly, in thicker lay- 

 ers, moist, glistening, and easily removed. In bouillon the 

 xerosis bacillus produces no clouding, with only small 

 flakes at the bottom. The alkalinity is not increased. 

 The Hofmann-Loffler bacillus grows as distinct, slimy 

 substances at the bottom of the tube, with rapid clouding 

 of the bouillon and increase of the alkalescence. On blood 

 serum the xerosis bacillus grows more rapidly than on 

 agar, but still slowly, forming dry colonies. The Hof- 

 mann-Loffler bacillus grows much more rapidly and with a 

 more moist growth, only slightly slower than the diphtheria 

 bacillus. He says that so far attempts have been unsuc- 

 cessful to change the form of one of these growths into 

 the other through long-continued cultivation, and it is 

 impossible to speak of entire identity ; yet he holds it as 

 not impossible that such identity may in time be demon- 

 strated. He is inclined to believe, contrary to Schanz, 

 that he was dealing with two forms of one family of organ- 

 isms. 



Heimersdorff (42) investigated the value of Neisser's dif- 

 erential staining method for the rapid diagnosis of diph- 

 theria of the conjunctiva. At the University' eye clinic, 

 at Breslau and Rostock, all cases of conjunctivitis crouposa 

 are tested according to the Neisser method. He has found 

 the test most reliable when employed with fresh cultures 

 nine to sixteen hours old. In order to obtain a positive 

 diagnosis he advises the simultaneous inoculation into 

 animals. So far the diagnoses made by the Neisser 

 method of staining were substantiated by the inoculation 

 tests. He calls attention to the importance of having a 



