LEE BARKER WALTON 25 



and A. pedatus among forms whose position is doubtful, 

 suggesting possible affinities with Tokophrya and 

 Nuclearia, noting at the same time the desirability for 

 further study. Until a better knowledge is obtained of 

 their affinities, however, it seems advisable to consider them 

 under the genus Actinolophus. 



The following summarizes our present knowledge of 

 the group and indicates the position of A. viimittis in 

 respect to the other species. 



Genus ACTINOLOPHUS, Schulze 



1874 Actinolophus, F. E. Schulze, Arch. mikr. Anat. v. 10, p. 3 92. (?) 1893 

 Actinospha'ridium, O. Zacharias, Forschungber Plon, v. 1, p. 15. 1896 Actinolo- 

 phus, Schaudinn, Das Tierreich, Fieliozoa, Berlin. 



Body spherical or oval, provided with a pedicle the 

 length of which is usually much greater than the diameter 

 of the body. Body generally (always?) provided with a 

 gelatinous envelope through which the fine pseudopia are 

 extended. Nucleus excentric contractile vacuole (?). 



The following table will serve to separate the forms: 



A^ Pseudopodia not knobbed at the extremity. 



B^ Pedicle 3-4/a in diameter, marine forms, 



A. peduncidatus 



B- Pedicle not more than 2jjl in diameter, fresh water 

 forms, 



C^ Body ovoid, diameter 18jLt, length 23/a, 



A. pedatus 



C- Body spherical, diameter 12/x, A. minutus 



A- Pseudopodia knobbed at extremity, diameter 30/x, 

 fresh water forms, A. capitatus 



1. A. PEDUNCULATUS, Schulze, 1874 A. p. F. E. Schulze, Arch. mikr. 

 Anat., V. 10, p. 392, f. 1-9. 1896 Schaudinn, Das Tierreich, Heliozoa, Berlin, p. 11. 



Length of body, up to 30/x, length of pedicle up to 

 lOOyu,, diameter of pedicle 3-4/ia. 



Marine, Baltic Sea. 



2. A. PEDATUS, (Zach.) 1893 Actinosphceridium pedatum, Zacharias, For- 

 schungber. Biol. Stat. Plon., v. I, p. 15, f. 9a, 9b. 1896 ? Actinolophus pedatus, 

 Schaudinn, Das Tierreich, Heliozoa, Berlin, p. 11. 1904 ? Actinosphceridium peda- 

 tum, (? Nuclearia caulescens), (? Tokophrya), Penard, Les Heliozoaires d'eau douce, 

 p. 318. 



