78 DAVENPORT ACADEMY OF SCIENCES. 



Apparently this species is not widely distributed over the state 

 nor is it an abundant form. It has been found in stagnant pond 

 water associated with ParamcEchmi. 



Trichocysts are well developed. 



I.OXOCEPHAI.US Ehrenberg. 



Body elongate-oval, posterior border rounded, anterior border 

 obliquely truncate and bent to one side. Near the anterior end 

 on one or both sides of the organism are borne one or more short 

 setae curved forward. From the posterior border extend one or 

 more long setae. Oral opening in the anterior truncated border, 

 but indistinct. 



lyOXOCEPHALUS GRANULOSUS S. K. 



Body elongate, nearly cylindrical, the anterior extremity trun- 

 cate and slightly' curved, a short curved seta borne on either side 

 of the body near the anterior extremity. One long, straight 

 seta projecting from the posterior border. Nucleus spherical, 

 centrally located. Contractile vesicle posterior to the luicleus. 

 Endoplasm granular. 



Eength, 40-70 microns. (Fig- 125, PL XVI.) 



Often found in great quantities in pond water among decaying 

 vegetable matter. The oral opening is on the oblique anterior 

 border although quite indistinct; its presence, however, may be 

 indicated by the fact that this region is slightly protruded at 

 times as if the mouth were being expanded. 



Conjugation of this species often occurs in infusions, the 

 oblique anterior borders being coalesced during the process. At 

 times the usually compact spherical nucleus ma}^ be found to be 

 separated into from four to six small, round masses lying close 

 together in the cytoplasm. This may represent a condition 

 following conjugation. 



Reproduction takes place by transverse division. 



URONEMA Dujardin. 



Ovate, or elongate. Oral aperture ventral, with an extensile 

 membrane. Cilia of general surface vibratile. One or more long 

 setae extending from the posterior border. 



