LIVING SPIROCHAETES 







when it swam oflE in the ordinary fashion (Cf. Fantham, I. 

 1908, p. 46). 



Another commonly occurringmovement is that whereby the 

 organism assumes the position of the limbs of a siphon tube, 

 such as is used in barometers (figs. 3-6). One end of the para- 

 site moves rapidly so that a long hmb and a sliort hmb of the 

 tube are seen (figs. 3, 4). Reversai of the direction of movement 



Fias. 3-7. Sketches ot a single Spirochaeta anodontae looking like the anus of a baroiiietcr tube 

 The leiigth of the linilis alters, limb A at first long, beconiing the shorter linib, 

 wliile limb B becomes the longer one, and vice-versâ. The organism flnally 

 straightened (Fig, 7.) and swam away. 



occurs, and by a wave of contraction passing in the opposite 

 direction from that which initiated the first movement, the 

 organism now extends so that the previously long limb beco- 

 mes converted into the short one (figs. 5, 6) and vice-versâ. 

 Thèse two movements were performed l>y one spécimen of 

 S. anodontae eighteen times in two and a half minutes. At the 

 end of this period the organism straightened and swam away 

 (fig. 7). Inasmuch as thèse movements of the parasites occur 

 within the style substance (their natural médium), and at the 

 same time as other spécimens in the field are progressing 

 in the usual fashion, this particular movement is not abnormal, 



