GENERAL CHARACTERS OF SPIROCH^TES. 51 



ity. It would be natural to expect that in so well- 

 marked a condition as the primary chancre, which 

 appears to be produced by some intense irritant, 

 there would be found large numbers of the causal 

 organisms. As a matter of fact, spirochaetes are al- 

 most invariably scanty in the tissues forming the 

 chancre, and in many instances observers have failed 

 altogether to find them. (Their presence on the sur- 

 face of the ulcer is of comparatively little impor- 

 tance, in view of the ubiquity of similar organisms.) 

 Others have failed to find the spirochaete in blood 

 from a syphilitic case, which was definitely proved to 

 be infective. The possibility of the existence of other 

 stages of the parasite, e. g., granules or coccoid bodies 

 (p. 40), must, however, be borne in mind. 



Again, spirochaetes may be present in the organs 

 of a syphilitic patient without apparently giving rise 

 to any anatomical changes ; as, for example, in an eye 

 which appeared quite healthy (Bab). In considering 

 the striking abundance of spirochaetes in still-born 

 syphilitic foetuses it must be remembered that such 

 bodies may be found full of other (bacterial) organisms, 

 scattered throughout all the tissues; and also that 

 Karlinski found spirochaetes distributed throughout the 

 tissues of a foetal pig, having there presumably spread 

 out from the intestine (see Fig. 57). 



The presence of the spirochaetes in gummas, which 

 are not supposed to be infectious, is somewhat curious, 

 for while this non-infectivity might be explained on 

 the ground that the spirochaetes here found are usually 

 few and degenerate, yet if they are the cause of the dis- 

 ease at this stage, they must be of very notable virulence, 

 since a gumma consists of a considerable mass of inflam- 

 matory tissue and may undergo rapid degeneration and 

 softening, both presumably due to active micro bial 



