36 DAVENPORT ACADEMY OF SCIENCES. 



The species, as most others of the genus, was exceedingly 

 minute. From near the anterior extremity of the elongate-oval 

 body arose two flagella, the anterior one vibratile, the slightly 

 longer posterior one trailing. 



A contractile vesicle was present anterior to the middle of the 

 body. The nucleus could not be detected. Movements oscilla- 

 tory. Habitat, stagnant water. 



Length of body, 15 microns. 



Order, POI.YMASTIGIDA. 

 Family, POLYMASTIGID^. 



TREPOMONAS Dujardin. 



Irregular in form but usually rounded posteriorly, with lateral 

 anterior lobes when seen from a lateral point of view. Flagella 

 two, equal in length, one arising from each lateral border. 



Trepomonas agilis Duj. 



Body exceedingly irregular in shape, different appearances 

 being presented from different points of view; when viewed lat- 

 erally the body is rounded posteriorly, expanding anteriorly into 

 two broad wing-like lateral lobes, which curve backward nearly 

 to the center of the body. Flagella two in number, one arising 

 from the posterior tip of each lateral lobe-like expansion. 



Length, 10-20 microns. 



This species is one of the smallest of free-swimming Protozoa 

 to be found in this state. Its movements are very rapid and dif- 

 ficulty is often experienced in making a satisfactory study of it 

 in the living condition. The lateral view as described above and 

 illustrated by Fig. 46, PI. VII, is the one by which the organism 

 is most readily recognized. From other points of view various 

 impressions as to its form are given, and when in rapid motion 

 the body often has the appearance of being spirally twisted. 



No oral aperture is visible and probably food may be ingested 

 at any point in the surface. 



Found in pond water, widely distributed. 



Order, EUGLENIDA. 

 Family, EUGLENIDA. 



EUGLENA Ehrenberg. 



Body elongate, changeable in form. Endoplasm usually bright 



