Jan., 1905.] Actinolophus minutus. 263 



3. A. minuiuij, n. sp. 



Body spherical, diameter 12fx including gelatinous envelope 

 approximately 1/x thick. Length of pedicle 70/x, diameter 1/u.. 

 Extremely fine short pseudopodia of about 2/x in length extend 

 beyond the envelope on all sides. Nucleus suboval situated in 

 the inferior part of the body. Contractile vesicle (?). Base of 

 pedicle (in the form studied) imbedded in a gelatinous mass 

 10-12/A in extent containing small algae, etc. 



Gambier, Ohio, U. S. A. 



A single specimen observed Oct. 29, 1904, in sediment from 

 an aquarium jar containing Hydra jusca, the entire contents of 

 the jar having been collected Sept. 13. 1904, in the Kokosing 

 River at Gambier and subsequently covered with a glass plate for 

 the purpose of preventing too rapid evaporation. The form was 

 under observation at intervals during a period of four hours. 



4. A. capitatus, Penard. 1890 A. c. Penard, Jahrb. nassau. Ver. . v. 

 43 p. 16 t. 1 f. 11. 1896 A. c. Schaudiiin, Das Tierreich, Heliozoa, Berlin, 

 p. 12. 1901 A. p. Sand. Etude nionographique sur le groupe des Infu- 

 sorres tentaculiferes, Ann. Soc. Beige de Microscopic. 1904 A. c. Penard, 

 Les Heliozoaires d'eau douce, Geneva, p. 316. 



Diameter 30/a, length of pedicle 90/a. Nucleus (?) , Contractile 

 vesicle, Pseudopodia few in number, knobbed. 



In fresh water, Germany. 



Penard described this species in 1890 from a single individual 

 referring it to the genus Actinolophus although noting its close 

 relationship with the tentaculiferous infusoria. Sand, 1901, in 

 his study of that group came to the conclusion that A. capitatus 

 was nearer related to the Heliozoa than to the Suctoria for the 

 following reasons, (a) the pedicle resembles that of Clathrulina 

 elegans, (b) the pedicle does not penetrate into the gelatinous 

 envelope as in Tokophrya limhata one of the Suctoria, (c) the 

 nucleus is excentric, (d) the species closely resembles A. pedun- 

 culatus. Penard, 1904, in his paper on the fresh water Heliozoa, 

 after having examined several more specimens which he remarks 

 are exceedingly rare, insisted on the suctorian nature of the form, 

 maintaining that the points raised by Sand have little value. 

 Penard at the same time suggests the desirability for a further 

 study of the form. Consequently it seems advisable at present 

 to allow it to remain in the genus Actinolophus. 



BIBLIOGRAPHY. 



ScHULZE, F. E. 1874, Rhizopodienstudien, Arch, f, mikr. Anat., v. 10. 



Penard, Eugene, 1890, Ueber einige neue oder wenig bekannte Pro- 

 tozoen, jahrb. Nassau Ver. f. Naturk. Jahrg. 43. 



Zacharias, O. 1893, Forschungsber. Biol. Stat. Plon, v. 1. 



ScHAUDiNN, Fritz, 1896, Das Tierreich, Heliozoa, Berlin. 



Sand, Rene. 1901, Etude monographique sur le groupe des Infusoires 

 tentaculiferes. Ann. de la Soc. Beige de Microscopic 



Penard, Eugene. 1904. Les Heliozoaires d'eau douce. Geneva. 



Kenyon College, Gambier, Ohio. 



