322 Illinois State Laboratory of Natural Hisiory. 



20. A. sol Ehrbg. 



This occurred only during the warmer half of the year, 

 from Jun^ to October, largely in collections from among 

 vegetation, where it was on one occasion quite common. A 

 few were found in lake towings. 



ACTINOSPEUERIUM STEIN. 



Body spherical, with numerous long tapering radiating 

 pseudopodia ; protoplasm vacuolated, vacuoles of the ectosarc 

 larger than those of the endosarc, the division between endo- 

 sarc and ectosarc distinctly marked. Nuclei numerous ; 

 contractile vacuoles located at the periphery. 



21. A. eichhornii Ehrbg. 



This interesting and fine species was seen only a few times, 

 appearing in towings from the river and Dogfish Lake from 

 July to September. 



Order CHALARATHORACA. 

 Raphidiophrys Archer. 



Isolated, or united into colonies. Body spherical, with 

 numerous fine, long, straight, radiating pseudopodia ; division 

 between endosarc and ectosarc not distinct. One or more 

 nuclei. Surface layer densely filled with fine, straight or 

 curved spicules, tangentially arranged. 



22. R. pallida Ehrbg. 



Found in small numbers in towings from substation C, in 

 Quiver Lake, during July and August. 



23. R. elegans Hertw. Less. 



Bare, occurring only in September, in towings from C. 



Class MAST IGOPH OKA. 



Order FLAGELLATA. 



Suborder MONADINA. 



Family HETEROMONADIDiE. 



Subfamily Dendromonadinje. 



Anthophysa Bory. 



Zooids minute, obliquely pyriform, united into round 

 clusters of fifty to sixty, which are borne upon the extremities 



