78 WISCONSIN PETTOPLANKTON 



Otter (rrr), Pokegama (2) (r), Rainbow (1) (r), Round (3) (rr), Sand (4) 

 (sss), Taylor (r), Upper Nashotah (r), Wildcat (sss). 



This species is quite unlike other members of the genus since the 

 processes are much more delicate and the cells larger. 



CHRYSIDASTRUM Lauterborn 1913. 



Cells joined to one another by pseudopodial processes and arranged 

 to form free-floating linear colonies of 2-16 cells that are not enclosed 

 by a gelatinous envelope. Cells spherical, with the periplast undiffer- 

 entiated but extending into several long, delicate, pseudopodia-like pro- 

 cesses. Chromatophore single, central, and laminate to band-shaped. 



Reproduction unknown. 



CHRYSIDASTRUM CATENATUM Lauterborn. PI. 14, Figs. 7-8. 



in Pascher, D. Siisswasserfl. Deutschl., Qsterr. u. d. Schw. 2, Flagellatae 2: 91, 

 fig. 144. 1913. 



Specific characters the same as those of the genus. (Euplanktont). 

 Diam. cells (without processes) 12-15 /A; (with processes) 45-60 /*. 



Kitten (rr), Mud (2) (rr), Wildcat (rrr). 



The cell shape is quite like that of Chrysamoeba but the definite or- 

 ganization into a linear colony and the single laminate chromatophore 

 are points of difference. The alga should also be compared with Rhizo- 

 chrysis planctonica Pascher. 



