FLAGELLATE PROTOZOA (MASTIGOPHORA) 



263 



156 (155) Forming annular colonies; individuals closely united. Flagella 



two, unequal Cycloncxis Stokes. 



Representative species. . . . Cycloncxis annularis Stokes 1886. 



From ten to twenty zooids, not in contact in older colonics, leav- 

 ing a central, circular space. Zooids obovate, about twice as long 

 as broad. Length of zooid 10 to 15 m- Marsh water. 



Fig. 434. Cycloncxis annularis. X 625. (After Conn.) 



tXjx 



157 (138) With a lorica 158 



158 (163) Not forming colonies 159 



159 (162) Lorica sessile 160 



160 (161) Lorica beaker-shaped; usually with a peristome process. 



Epipyxis Ehrcnberg. 

 Representative species. . . . Epipyxis utriculus Ehrcnberg 1838. 



Lorica is truncate or slightly everted anteriorly, widest centrally and pointed 

 posteriorly. Body occupies about one-half the cavity of the lorica. and is at- 

 tached by a thread-like pedicel to one side of the lorica. An eye-spot usually 

 present. Nucleus central; contractile vacuole anterior. 



Length of lorica about 40 /x. Attached to water-plants. 



Fig. 435. Epipyxis utriculus. X 650. (After Stein.) 



161 (160) Lorica urn-shaped. . 

 Representative species. 



Chrysopyxis Stein. 



Chrysopyxis urceolata Stokes 1886. 



Zooid occupying the center of the lorica, but in no way attached to it. 

 Flagella two, long, diverging. Yellow chromatophores often present. Nu- 

 cleus centrally located; contractile vacuole ixisterior. Length of lorica \2 fx. 

 Attached to algae. 



Fig. 436. Chrysopyxis urceolata. x uoo. (After Stokes.) 



