8o DAVENPORT ACADEMY OF SCIENCES. 



COLPODA HELIA StokeS. 



Body elongated, bean-shaped, both extremities evenly rounded, 

 the anterior one curved ventrally. Oral aperture ventral, about 

 one-third the length of the body from the anterior end. Pharynx 

 short, curved. Nucleus oval, central. Contractile vesicle pos- 

 terior, with radiating sinuses. 



Length, I00-I20 microns. (Fig. 129, PI. XVII.) 

 Frequently found in abundance in pond water. 



C01.PODA SAPROPHiLA Stokes. 



Body somewhat semi-circular when viewed laterally, convex 

 dorsally, flattened ventrally. 



Oral aperture near the center of the ventral surface, leading 

 into a short, curved pharynx. Nucleus near dorsal border. Con- 

 tractile vesicles one or more, posteriorly situated. 



Length, 30 microns. (Fig. 130, PI. XVII.) 



When undisturbed the organism usually rests on its side so that 

 the recurved pharynx is very conspicuous. ^.The dorsal surface 

 obliquely striated, the ventral border of the anterior -extremity 

 being more or less deeply notched, the notches corresponding to 

 the striations. 



Reproduction, as stated by Stokes, takes place by division or 

 by spore formation during the encysted state. 



Found in infusions of pond water, but not abundant in the state. 



CoLPODA FI.AVICANS Stokes. 



Body kidney-shaped, rounded, inflated and wider posteriorly, 

 compressed anteriorly. Convex dorsally, flattened or concave 

 ventrally. Oral aperture near the center of the ventral surface. 

 Pharynx short, recurved. Nucleus central. Contractile vesicle 

 single, posterior. 



Length, 65 microns. (Fig. 131, PI. XVII.) 



The species has been found in this state in damp moss taken 

 from trees, also in hay infusions. It is not an abundant form. 

 The endoplasm is commonly filled with spherical food-ma.sses. 



COLPODA CAMPYI^A StokeS. 



Body elongate-reniform, three or four times as long as broad, 

 the anterior extremity curved slightly toward the ventral aspect, 



