smith: infusoria of Kansas. 157 



scattered, varying; in number with the size of the individual. Macro- 

 nucleus single, situated posterior to the inner end of the pharynx. 



This is a very common species, found usually in pond water. 



Sizes given vary from 100 to 398 microns. Length of type specimen, 

 117 microns. (Fig. 13, plate XXXV.) 



Chilodoii megalotrocha Stokes. 



The form illustrated by fig. 16, plate XXXV, seems to be identical 

 with Chilodoii megalotrocha as figured by Conn in his The Protozoa of 

 the Fresh Waters of Connecticut. It is a very small, clear animal, cor- 

 responding to the generic description. Pharynx supported by minute 

 rods, siuated anterior to the middle of the ventral surface. Macronucleus 

 .single, subcentral. Usually two contractile vacuoles. 



A very common species, found in both pond water and hay infusions. 



Length of type specimen, 48 microns. (Fig. 16, plate XXXV.) 



Suborder Trichostomina. 



Mouth permanently open. Undulating membranes usually present in 

 mouth region. 



Family Chiliferid^. 



Mouth never posterior to middle of the body. Undulating membrane 

 usually present in connection with mouth. Pharynx short when present, 

 often lacking. Peristomal area either entirely lacking or but faintly 

 developed. 



Genus Frontonia Ehr. 



Body elongated oval, cylindrical or slightly flattened dorsoventrally. 

 Extremities either rounded or pointed. Mouth permanently open, 

 located anterior to the middle of the body. Left-hand border of the 

 mouth with undulating membrane; right-hand border with elevated 

 ridges. A groove extends from the mouth posteriorly, often to the ex- 

 treme end of the body. Pharynx short and inconspicuous. Cuticular 

 surface longitudinally striated with rows of fine cilia. Trichocysts 

 abundant, lacking in mouth region. One or two contractile vacuoles. 

 Macronucleus oval; one to many micronuclei. 



Frontonia leucas Ehr. 



Body elongated oval, anterior extremity widest. Rounded anteriorly, 

 pointed posteriorly. Mouth anterior to the middle of the body, an un- 

 dulating membrane on its left-hand border; right-hand border with 

 ridges; a groove extending from the mouth well down the body. Cilia 

 very fine. Trichocysts abundant. 



This species was found frequently in pond water. 



Average length given, 275 microns. Length of type speci.nen, 240 

 microns. (Fig. 22, plate XXXVII.) 



Genus Colpidium Stein. 



Body oval or reniform, incuived ventrally, arched dorsally. Posterior 

 extremity somewhat broader. Mouth located in a depression some dis- 

 tance from the anterior end. Pharynx tubular with projecting undulat- 

 ing membrane. Anus terminal. Contractile vacuole terminal or for- 

 ward on the dorsal side. Macronucleus spherical; micronucleus single, 



