38 DAVENPORT ACADEMY OF SCIENCES. 



cle and eye-spot in the anterior region near the base of the flagel- 

 lum. 



Length of body, 100-200 microns. (Fig. 52, PI. VIII.) 

 Eiiglcna spirogyra is the largest species of the genus coming 

 under my observation. The body ornamented in a spiral fashion 

 is frequently found in a twisted and contorted condition and the 

 bead-like elevations may be partially or entirely wanting. It is 

 a much more sluggish organism than Eiiglciia viridis, the flagel- 

 lum .being comparatively short. Usually found in fresh water 

 among algae, mostly solitary. 



EUGLENA ACUS Ehr. 



Body exceedingly elongate, anterior end truncate, posterior 

 end sharply pointed. Flagellum short. Nucleus central, con- 

 tractile vesicle anterior, pigment spot and amylaceous bodies con- 

 spicuous. 



Length of bod}', 75-150 microns. (Fig- 54, PI- VIII.) 

 The great length compared with the width and the apparent rig- 

 idness of the body may readily distinguish this species from other 

 members of the genus. The organism may exceed in length 

 twelve times its greatest breadth and the body is seldom or never 

 flexed. 



Usually the starch-like bodies appear as elongate rectangular 

 structures, one anterior and the other posterior to the nucleus. 

 The flagellum is very short and movement of the animal, when 

 it takes place, is very slow. 



F'ound nearly everywhere in pond water, often abundantly 

 among algce, etc. 



EuGLENA DESES Ehr. 



Body elongate, worm-like, capable of amoeboid movements. 

 Flagellum short. Nucleus, contractile vesicle and pigment spot 

 present. Amylaceous bodies usually scattered throughout the 

 endoplasm. Color green. 



Length of extended body, 50-100 microns. (Fig. 53, Pi. VIII.) 

 As an organ of locomotion, the flagellum of Eiigkna dcscs is of 

 little value, movements usually being confined to exceedingly 

 slow amoeboid contortions of the body. In young individuals the 

 flagellum may be wanting. The species is usually solitary in its 

 habits, being found not infrequently in fresh water among algse. 



