296 



BACILLI PATHOGENIC IN MAN. 



Criticism of 



have been 

 the present 



round granules staining with methylene blue, *5 to 1 p. 

 in size, partly enclosed in the red blood corpuscles, 

 partly lying free between them ; in addition to these 

 granules, there were ring-shaped bodies of almost 

 double the size. When this blood was inoculated on 

 nutrient agar, he obtained a pure cultivation of a 

 species of micrococcus, growing in the form of a white 

 gelatinous mass ; in addition, in one case he obtained 

 yellowish growths of micrococci. No positive results 

 were obtained by experiments on animals with either of 

 these species ; these experiments have, however, only 

 as yet been made on rats, and are not concluded. The 

 method employed by Von Sehlen for making the cultiva- 

 tions affords no guarantee of the exclusion of accidental 

 micro-organisms. Examinations of soil and air made 

 by Yon Sehlen in malarial regions and in regions free 

 from malaria led, in both cases, chiefly to the isolation 

 of two species of bacilli and cocci, the latter of which 

 grew in a similar manner to those cultivated from blood. 

 and were likewise without any marked action on the 

 animals experimented on. 



A consideration of these various facts leads us to fie 

 conclusion that the cultivation experiments have not as 

 ve t yielded any trustworthy results as to the organisms 

 which take part in the malarial infection. The obser- 

 vations as to the presence of large bacilli in the blood 

 of patients suffering from malaria are undoubtedly 

 erroneous, as shown by the control investigations which 

 have been subsequently made. We cannot at once say 

 the same as regards the results obtained by Laverau, 

 by Marchiafava and Celli, and by Yon Sehlen, which 

 agree with regard to the constant occurrence of peculiar 

 bodies in the interior of the red blood corpuscles ; we 

 can only say that Laveran evidently obtained a number 

 of forms, as the result of errors in preparation, and mis- 

 took these forms, as well as the altered blood corpuscles, 

 for stages of the development of a micro-organism. As 

 the result of the investigations made by Marchiafava and 

 Celli, the alteration of the red corpuscles seems to be, 

 to some extent, a constant occurrence in malaria ; it is, 



