CULTIVATION OF PARASITIC AMCEBJ2. 63 



with pure cultures of bacteria and to have produced 

 in monkeys typical symptoms of the disease by the 

 use of such cultures. While there can be no question 

 that they were able to cultivate amoebae from the f eces 

 of dysentery cases it is still uncertain just what species 

 were obtained in this way, and while lesions were 

 undoubtedly produced by the mixed cultures of 

 amoebae and bacteria, the authors could not, with their 

 methods, be sure of excluding the spores of En- 

 tamoeba histolytica, or the encysted forms of other 

 amoebae pathogenic to the animals used in their experi- 

 ments. As they did not accept Schaudinn's classifi- 

 cation, they made no differentiation between patho- 

 genic and free-living amoebae, and many of their 

 photomicrographs of the organisms from cultures 

 prove that they were dealing with ordinary free-living 

 species. 



Walker, in 1908, following and amplifying the 

 methods of Musgrave and Clegg, claims to have suc- 

 cessfully cultivated numerous amoebae, including 

 parasitic species, but his description of the life cycle 

 of the parasitic forms does not agree with that of 

 Schaudinn, Doflein, Ltihe, Viereck, and many others 

 who have thoroughly studied the methods of repro- 

 duction of amoebae found both in health and disease. 

 It is more than probable that the amoebae cultivated 

 by Musgrave and Clegg, and by Walker, were free- 

 living species occurring accidentally in the feces. 



