xii Contents. 



PAGE 



killed by Heating or Drying — The Trachelius ovum — 

 Mode of Swimming — Method of Viewing — By Dark- 

 ground Illumination — Curious Digestive Tube with 

 Branches — Multiplication by Division — Change of Form 

 immediately following this Process — subsequent Ap- 

 pearances 128 



CHAPTER XIII. 

 Conclusion. — Remarks on Classification, &c. . . . 140 



