EU CI LI AT A, HOLOTRICHIDA 357 



Genus Dysteria Huxley. Body ovoid on the whole, constant. 

 Colorless or variously colored. Ventral side narrowly ciliated. 

 Cytostome toward one side near the anterior end with a distinct 

 basket. A spinous projection from a point near the posterior 

 end. A globular macronucleus; contractile vacuoles several. 

 Marine. 



Dysteria lanceolata Claparede and Lachmann (Fig. 153, j). 

 Body 45 to 70 microns long. Marine. 



Dysteria armata Huxley. Body length 40 to 100 microns. 

 Marine. 



Genus Phascolodon Stein. Body rounded; anterior end 

 broadly truncate and curved dorsally; posterior end narrowed. 

 Dorsal surface convex; ventral surface flattened. Ciliation 

 general. Cytostome near the anterior end on the ventral side 

 and with a pharyngeal basket. Two contractile vacuoles ven- 

 tral. Fresh water. 



Phascolodon vorticella Stein (Fig. 153, k). About 80 to 90 

 microns long. Fresh water. 



Genus Scaphidiodon Stein. Body spheroid or boat-shaped; 

 colorless. Dorsal surface convex ; ventral surface flat. Posterior 

 end drawn out into a spinous projection; the anterior edge 

 possesses a lip-like border. Cytostome near the anterior end 

 with a pharyngeal basket. Macronucleus oval, central. Con- 

 tractile vacuoles. Marine. 



' Scaphidiodon navicula Stein (Fig. 153, /). About 150 microns 

 long. In salt water. 



Genus Trochilia Dujardin. Body small, ovate. Dorsal sur- 

 face convex; ventral surface flat. Anterior portion bent toward 

 the left. There is a movable spinous structure attached at the 

 posterior end. Cilia confined to a subcentral, curved, band-like 

 area on the ventral surface. Cytostome in the anterior half of 

 the body. Cytopharynx visible. There is a long cirrus near the 

 cytostome. Fresh or salt water. 



Trochilia palustris Stein (Fig. 153, m). Body about 30 

 microns long. Fresh water. 



Genus Aegyria Claparede and Lachmann. Body medium 

 large. General appearance similar to Chilodon. Colorless or 

 variously colored. ■ Ventral side flattened or slightly convex, 

 longitudinally striated. At the posterior end, there is a movable 



