74 



SPIROCILETES. 



brane, Schaudinn who attributed to it such a membrane 

 probably having mistaken for it the loose periplastic 

 sheath. It exhibits screw-like movements, but also 

 creeping and feeling (kriechend, tastend) movements, 

 while the contraction of its sheath may lead to a thicken- 

 ing and thinning of the body at different places. Its 

 mode of multiplication is not known, but it has been 

 seen to break up transversely. 







IG. 58. Spirochaeta plicatilis. (Schaudinn.) 



The most recent description of this organism is due 

 to Zuelzer, according to whom it is round in section, 

 with a central axial thread of elastic substance and a 

 simple spiral twist. A round refringent body is placed 

 at the central point of each wave, and fine granules of 

 volutin are also present. Sometimes a terminal gran- 

 ule is seen at one extremity, from which the axial 

 filament starts. The length may reach 500/1 and the 

 breadth /*. The ends may be rounded or sharp. 

 Transverse division occurs, either two or more frag- 



