ACTINOLOPHUS MINUTUS, A NEW HELIOZOAN, 



WITH A REVIEW OF THE SPECIES 



ENUMERATED IN THE GENUS^^^- 



While examining late in October some sediment in a 

 jar containing Hydra fusca collected September 17, 1904, 

 in the Kokosing River, attention was attracted by a small 

 stalked form of heliozoan-like appearance. This, a single 

 example of which was observed, on more careful study 

 proved referable to the genus Actinolophus (Heliozoa) 

 the representatives of which are not met with frequently, 

 none to the knowledge of the present writer having thus 

 far been noted in America. 



Although there is considerable uncertainty as to the 

 exact relation of the species constituting the group to the 

 other Protozoa, the characteristics of the form in question 

 appear to merit record, differing as it does from A. capi- 

 tatus Penard through the absence of knobbed pseudopodia 

 as well as in its much smaller size, and from A pedatus 

 (Zach.) by the spherical form of the body which is ovoid 

 in the latter and much larger than the body of A. mimttus. 



Schulze, 1874, formed the genus Actinolophus for the 

 reception of A. pedunculatus a marine form from the 

 Baltic Sea described by him. Penard, 1890, described A. 

 capitatus from a single individual suggesting its close 

 relationship with the tentacliferous infusoria (Suctoria). 

 Zacharias, 1895, in a brief description, called attention to 

 a new Heliozoan, Acf^nosphceridium pedatus which 

 Schaudinn, 1896, in his monograph of the Heliozoa, 

 placed provisionally in the genus Actinolophus, recogniz- 

 ing for that genus three species, two of which were of 

 doubtful value. Penard, 1904, in his valuable monograph 

 of the fresh water Heliozoa, mentions both A. capitatus 



^Read before the Ohio State Academy of Science Nov. 26, 1904. 

 ♦Reprinted from The Ohio Naiuralist, vol. 5 (1905), pp. 261-263. 



