5i6 MICRO-ORGANISMS AND DISEASE [CHAP. 



multiply. If it be contended that they, being normal con- 

 stituents of the healthy body, cannot be the parasites of 

 cancer, it might be answered that the amoebo-sporidia of 

 Pfeiffer are not identical wdth them ; that the normal white 

 blood cells are one species, and that the amoebo-sporidia are 

 a different pathogenic species. I am merely showing the 

 kind of argument that Pfeiffer could bring forward if he 

 chose to go beyond his ipse dixit. And nothing is gained 

 by studying Pfeiffer's photograms (1. c, Plate i, Figures 

 I — 4), representing sections through epithelial cancer of the 

 pectoral muscle and the lip of man, which are submitted by 

 him as illustrating amoebo-sporidia. What is represented by 

 him under a low magnifying power ( x 60) may be any- 

 thing ; whereas the appearances shown (Figure 4) under a 

 magnifying power of 600 are nothing else than a cluster of 

 nuclei, which may be those of epithelial cells or of leuco- 

 cytes. 



Pfeiffer's researches, indeed, though systematic and ex- 

 haustive so far as they refer to the nature and distribution 

 of coccidia and allied psorosperms, and to the various 

 sporidia in the animal kingdom, are extremely fragmentary 

 with reference to cancer in man ; there is practically no 

 satisfactory evidence of the presence of what Pfeiffer calls 

 spore forms in the cancer epithelial cells, or of the presence 

 of amoeba forms around them. 



One of the most striking facts in the large mass of the 

 literature on the subject of coccidia and psorosperms in 

 cancer is the absence of any well-authenticated sickle-like 

 bodies ; that is to say, of those characteristic bodies which, 

 according to the unanimous testimony of all those who have 

 investigated the life-history of the various parasitic and non- 

 parasitic coccidia and psorosperms (Leukart, Biitschli, 

 Eimer, L. Pfeiffer, and others), constitute one of the most 



