86 SOME MINUTE ANIMAL PARASITES 



the splitting of the group and the renaming of the 

 molluscan forms as Cristispira is not only un- 

 necessary but is misleading. 



The parasite of syphilis was first regarded as a 

 spirochsete, but later was renamed Treponema palli- 

 dum, because the coils of the body were said to 

 be fixed. Balfour recently has shown that Trepo- 

 nema is a "granule shedder " i.e., it produces 

 ovoid bodies just as spirochaetes do. In this case it 

 seems very probable that it is only the minuteness 

 of the organism that prevents full knowledge of its 

 internal structure, and that for the same reason its 

 coils appear fixed. There are undoubted affinities 

 between all the organisms mentioned, and it seems 

 far better to keep the older nomenclature and not to 

 attempt re-classification until the life-history of each 

 form has been fully elucidated. Building on an 

 insecure foundation has the disadvantage of causing 

 endless patching and emendation later, and the old 

 saying, " More haste, less speed," is as applicable in 

 protozoology as elsewhere. 



Much debate has also arisen as to the systematic 

 position of the spirochaetes. The medical world 

 and many of the leading zoologists regard them as a 

 new class of the protozoa, the Spirochsetacea, while 

 others consider them bacteria. It has been said 

 recently that the formation of ovoid bodies or 

 spores is evidence of their bacterial affinity, but no 

 one regards coccidia as bacteria, yet they also pro- 

 duce spores. However, the term spore is difficult 

 to define. The body structure of a Spirochaete is 

 probably more complicated than that of bacteria, 



