EDMONDSON — PROTOZOA OF IOWA. 4I 



this individual the caudal appendage was straight; seven longi- 

 tudinal ribs were present on either of the flattened surfaces, each 

 rib being thickly set with minute spines which pointed posteriorly. 

 Habitat, fresh water among diatoms. 



Besides the two species of Chloropeltis already referred to there 

 appears in this state another form which, in my opinion, should 

 be referred to this genus. 



The oval body, broadly rounded at each extremity, possesses 

 the characteristic elevation on the anterior border from which 

 arises a long flagellum. A small, conical projection arises from 

 the posterior border. The surface is grooved in an oblique direc- 

 tion. Usually the endoplasm is colored bright green although 

 colorless individuals are not infrequently seen. In these latter the 

 oblique markings are evident. This form is more abundant than 

 Chloropeltis hispidiila in this state but usually solitary in habits. 

 Habitat, fresh water. 



Length, 50-60 microns. (Fig. 60, PI. VIII.) 



TRACHELOMONAS Ehrenberg. 



Body inhabiting a hard, brittle lorica usually brownish in color. 

 Flagellum single, protruding through the single aperture. Endo- 

 plasm usuall}^ green, with nucleus, contractile vesicle and ej'e- 

 spot present. 



Trachelomonas piscatoris Stokes. 



Eorica flask-shaped, cylindrical, less than twice as long as broad, 

 surface clothed by numerous short, conical spines. Both extremi- 

 ties equally rounded, the anterior produced into a smooth, cylindri- 

 cal, neck-like prolongation, the border of which is deeply toothed. 



Length, 36 microns. (Fig. 64, PL IX.) 



The above description as given by Dr. Stokes well character- 

 izes a form frequently observ^ed in the waters of this state. 



Thirty-six microns has been observed by the writer to be the 

 approximate length of the lorica of the mature organism. Its 

 distribution over the state is general. Habitat, fresh water, 

 among aquatic plants. 



Trachelomonas cylindrica (?) Ehr. 



Lorica very elongate, cylindrical, surface smooth, anterior ex- 

 tremity produced into a short, tubular neck. Color usually brown. 



[Proc. D. a. S., Vol. XI. 1 t> [May 14, 1906.] 



