EDMONUSON — PROTOZOA OF IOWA. 35 



The species has been found many times usually attached to 

 aquatic plants. Fig. 49, PI. VII, illustrates an individual from 

 Johnson county. 



Commonly the number of zooids attached to one pedicle, as 

 observed by the writer, has been from four to eight. 



The stalk ma}' reach six or eight times the length of a single 

 zooid. 



MONOSIGA S. K. 



Not forming colonies. The body oval or spherical, .sometimes 

 .changeable in form, sessile or with a short stalk. Collar promi- 

 nent. Flagellum single. 



MONOSIGA STEINII S. K. 



Body ovate, wider centrally, tapering toward each extremity, 

 attached in a sessile manner to some support. Collar nearly 

 equalling the body in length. 



Length of bod}-, 12-15 niicrons. (Fig. 45. PI. VII.) 



The minuteness of size renders impossible a very satisfactory 

 study of this organism. It is found usually attached to the ped- 

 icle of some species of J 'orticclla. 



During the summer of 1905 it was found in abundance attached 

 to the stalk of \'orticcUa canipajuilaria in a running stream near 

 Iowa City. The species has also been observed attached to the 

 pedicle of Voriicc/la coiivallaria. As many as fifteen or twenty of 

 these minute collared flagellates may be .seen adhering to the 

 contractile stalk of a single \ ^orticclla. By the use of reagents a 

 centrally located, .spherical nucleus may be brought to view. 



Order, HETEROMASTIGIDA. 

 Family, BODONID^. 



HETEROMITA Dujardin. 



Body usually oval or elongate but changeable in form. Flagella 

 two in number, arising from the anterior or lateral borders of the 

 body, one directed forward vibratile, the other trailing. No dis- 

 tinct mouth. 



Hetkromita sp. 



Figure 50, Plate VII, represents a species observed in this 

 state which, without doubt, must be referred to this genus. 



