14 



PROTOZOA. 



Omitting Acinetidae, Claus's arrangement of the families is here 

 followed. 



Torquatella. 



Order II. FLAGELLATA. 

 MASTIGOPHORA. 



Body provided at its anterior portion with one or more long 

 flexible filaments [flagella], the ends only vibratile. Cilia occa- 

 sionally present. 



The flagella are never more than ten ; sometimes there is only 

 one, more frequently two. They serve for locomotion. Astasia 



