41 



finds its nearest ally in Anthophysa, (littering from that genus 

 principally in being tree swimming instead of fixed upon a stalk." 

 The -enera Chhimvdonmnas and Colpodella are represented at 

 Fi- I'd. I',. A hiu'hri- form than Monas is Codosiga (Fig. 17) in 



human parasites, i.e., Celcomn,,,,* urinaria C. intestinalis and 

 Trichomonas vaginalis. 



The second family of monads are the Astasiasa. Here belong 

 Astasia and Euglena (Fig. 18). The former genus is somewhat 



to Clark, during its a,mrl>oid retroversions becoming "contorted 

 into a shapeless, writhing mass." They have a conspicuous, red 

 so-called " eye-spot." A similar organ occurs in the zoospores of 



1. Monadina. Body small, rounded, naked or with a tough 

 membrane ; resembling the zoospores of algee, etc. 



2. Astasicea. Body naked and changeable like the monads, 

 only bearing flagella. 



