360 Illinois State Laboratory of Natural History. 



Order I. RHIZOTA. 



Family FLOSCULARIDiE. 



Floscularia Oken. 



Frontal lobes short, expanded, or wanting ; setfe very long 

 and radiating, or short and cilia-like ; foot terminated by a 

 non-retractile peduncle, ending in an adhesive disc. 



1. F. ornata Ehrlg. 



Infrequent. Found during September on Ceratophyllum at 

 substation L in Doghsli Lake. 



Family MELICERTIDiE. 



LiIMNIAS SCHRANK. 



Provided with a tube, which is usually dark colored, but 

 not made of pellets. Corona distinctly two-lobed ; dorsal 

 gap wide ; dorsal antenna minute. 



2. L. ceratophylli Schrank. 



This fine form was first found in an aquarium started with 

 dried mud from the bed of Phelps Lake, and in September 

 was discovered on Ceratophylliuii and Potamogcton from 

 Thompson's Lake. While the rotifer was expanded a con- 

 stant stream of fine particles kept moving away from 

 it, the movement being quite uniform and the direction defi- 

 nite, as if the stream were shot out of the nozzle of a hose. 



Cephalosiphon Ehrbg. 



Corona nearly circular; dorsal gap distinct; dorsal an- 

 tenna obvious ; ventral antenna3 absent, two dorsal hooks 

 enclosing the dorsal antenna. 



3. C. limnias Ehrbg. 



Infrequent, occurring in September on vegetation from 

 Thompson's Lake. 



CEciSTES Ehrbg. 



Corona a wide oval, indistinctly two-lobed ; dorsal gap 

 minute; dorsal antenna absent; ventral antenna3 obvious. 



