SMALLPOX, SYPHILIS, CANCER, ETC. 181 



phase of a polymorphic organism, in the same way that 

 grape-sugar solutions favour the gemma-stage of Mucor 

 racemosus. 



The parasite of syphilis and Synchytrium. It has been 

 shown in Chapter V that bird's-eye bodies occur in Synchy- 

 trium and in syphilis as well as in cancer. The series of 

 stages seen in Fig. 52 is almost identical with those of the 

 direct sporangium of the thistle- Synchytrium, Fig. 23 : 

 pycnoplasson, chasmato-plasson, &c. Looking again at 

 Fig. 52, z, and comparing it with the stages of Synchytrium 

 we should expect the succeeding stage of the parasite of 

 syphilis to be flagellate, and such I have no doubt is the 

 case. In S. endobioticum three different flagellate phases 

 occur. It may be that the monoflagellates of Siegel are the 

 zoospores, and the biflagellate spironeme the zygote of the 

 parasite. It seems to me that the most promising line of 

 inquiry to clear up the questions of the relation of the 

 spironeme to the other parasitic forms in syphilis and 

 other diseases is through the study of flagellate-diphtheria 

 of birds, combined with such study of syphilis as was well 

 begun in 1906 by MacLennan. 



Gummata. With regard to the histology of the gumma, 

 in 1895, I stated my opinion that much of the broken-down 

 material consists of parasites in a state of fatty degeneration 

 and compared them to similar bodies in cancer, e.g. in the 

 sarcoma of the testis, Fig. 31, in M.G. and S., also Part II, 

 Figs. 41 and 42. 



