40 DAVENPORT ACADEMY OF SCIENCES. 



process requires a long time. The nucleus, centrally located, is 

 usually concealed. A brilliant red pigment spot is placed near 

 the contractile vesicle. 



Figure 56, Plate VIII, illustrates a normal individual of this 

 species. Usually solitary in habits, found widely distributed in 

 fresh water. 



Phacus pyrum Ehr. 



Body pyriform, produced posteriorly into a straight, tail-like 

 prolongation. Surface obliquely grooved. Color green. 



Length, 38 microns. (Fig. 57, PI. VIII.) 



This species is often found in great numbers in fresh water 

 associated with Euglena viridis and aquatic plants of low rank . 



The nucleus is usually concealed. A contractile vesicle and 

 pigment spot are anteriorly located near the base of theflagellum. 

 In motion the body follows a meandering course, rolling on its 

 longitudinal axis. 



CHLOROPKLTIS Stein. 



Oval, sometimes flattened, posterior extremity tail-like, ante- 

 rior border with a small conical projection. Flagellum single. 

 Ktidoplasm green. Surface with or without striations. 



Chloropeltis ovum Khr. 



Body oval, cylindrical, with an anterior conical projection from 

 which arises a long flagellum, posterior extremity prolonged into 

 a straight, tail-like process. Kndoplasm green, usually enclosing 

 four amylaceous bodies laterally placed. Surface of the body 

 often striated. 



Length, 42 microns. (Fig. 58, PI. VIII.) 



Found in fresh water with Euglena viridis. Not an abundant 

 form in this state. 



Chloropeltis hispidula Eichwald. 



Body oval, flattened, with a tail-like projection. Surface of 

 the body ornamented with minute spines arranged in longitud- 

 inal rows. Kndoplasm green, with eye-spot. 



Length, 55 microns. (Fig. 59, PI. VIII.) 



This species is exceedingly rare in the waters of this state, as it 

 has been observed but once and that was in Johnson county. In 



