EUGLENOIDIDA, CHLOROMONADIDA 121 



Pyrenoids absent. Longitudinal fission. Occur with Euglena 

 and Phacus. Several species are known. 



Lepocinclis ovum (Ehrenberg) (Fig. 41, a). About 20 to 40 

 microns long. 



Genus Trachelomonas Ehrenberg. With a simple test which 

 often possesses numerous spinous projections. Sometimes yel- 

 lowish to dark brown in color. A single flagellum protrudes 

 from the anterior aperture, the rim of which is frequently thick- 

 ened to form a collar. Chromatophores are either two curved 

 plates or numerous discs. Paramylum bodies, if present, are 

 in the form of small grains. Stigma and pyrenoids are often 

 present. Multiplication by longitudinal fission; one daughter 

 individual retains the test and the flagellum, while the other 

 escapes through the flagellar aperture, forms a new flagellum 

 and secretes a test. Cysts common. Among algae. Specific 

 differentiation is based upon the test. Numerous species. 



Trachelomonas hispida (Perty) (Fig. 41, h). Ellipsoidal; 

 about 35 microns long. Test with numerous minute spines. 

 Aperture with or without a short neck. Brownish in color. 



Trachelomonas cylindrica Ehrenberg (Fig. 41, c). About 25 

 microns long. Test elongate, without spines. 



Trachelomonas armata Ehrenberg (Fig. 41, d). Body about 

 40 microns long. Subspherical; test surface finely punctate and 

 brown in color. Numerous short spines surround the aperture; 

 often with long spines along the posterior margin. 



Genus Cryptoglena Ehrenberg. Body rigid, flattened. Two 

 lateral band-form chromatophores; a single flagellum; nucleus 

 posterior. Among algae. 



Cryptoglena pigra Ehrenberg (Fig. 41, e). Body ovoid, 

 pointed posteriorly. Flagellum short; stigma prominent. About 

 12 microns long. 



Genus Ascoglena Stein. Encased in a flexible colorless to 

 brown test which is attached with its base to foreign object. 

 Solitary and without stalk. Body ovoidal, plastic; attached 

 to the test with its posterior end. A single flagellum protrudes 

 from the aperture end of the test. A stigma; numerous chroma- 

 tophores discoid; with or without pyrenoids. Reproduction as 

 in Trachelomonas. Cysts unknown. 



