2 H. B. FANTHAM. 
Affinities and Systematic Position : 
Affinities with the Bacteria P ee 2 SRS 
Affinities with the Protozoa ; ; - od 
A suggested New Class of the Protozoa . 5b 
Summary and Conclusions : ; : eh 
Appendices : 
I. On some points in the Chemistry of the Crystalline 
Style of Anodonta cygnea 0) 
II. Some Remarks on Wave-like Motion in Oreanisns = 63 
III. On the Possible Formation of Myonemes in Spirochetes 63 
Addendum j : : G4 
References to Literature : : ~ 66 
Explanation of Plates : : : - 69 
INTRODUCTION. 
Tuere are few more interesting unicellular organisms at 
present under investigation than those microscopic, yet most 
active, forms known as Spirocheetes, which lie on the border- 
line between animals and plants. They are, indeed, veritable 
members of Haeckel’s kingdom Protista, which—from their 
minute size and attenuate form—are most difficult objects for 
research. Little is known precisely of their structure, and 
their affinities are the subject of much discussion; hence the 
use of the term Protista in the preceding sentence. The 
wisdom of this classification for avoiding hard and fast lines 
where such do not naturally exist among the lowliest 
organisms, has now been recognised, and Schaudinn a few 
years ago founded a journal (‘ Archiv fiir Protistenkunde’) 
exclusively devoted to the publication of memoirs on such 
organisms, including Bacteria. And the study of these forms 
is of the highest economic importance. 
The famous French investigators, Laveran and Mesnil, 
regard these organisms as Bacteria, and in this view they 
are followed by Novy and his co-workers in America, who 
seem to regard the Spirochete of human relapsing fever (S. 
obermeieri) as belonging to the genus Spirillum. 
The late Dr. Schaudinn and the members of his school (for 
example, Prowazek, Hartmann, Keysselitz), on the other 
