WISCONSIN PHYTOPLANKTON 169 



PEDIASTRUM SCULPTATUM G. M. Smith. PI. 46, Fig. 1. 

 Bull. Torr. Bot. Cl. 43: 475, pi, 25, fig. 13. 1916. 



Coenobia oval to circular, of 8-16-32 cells. Interior cells with 4-6 

 straight sides, with a few interstices between the cells. Marginal cells 

 bilobed, with the lobes produced into two short divergent or parallel 

 processes. Cell wall covered with a network of very fine ridges. (Fac- 

 ultative Planktont). 



Diam. cells 10-15 /*. Diam. coenobia 80-150 /*. 



South Turtle (rr). 



PEDIASTRUM BORYANUM (Turpin) Meneghini. PI. 46, Figs. 2-7. 



Linnaea 14: 210. 1840; G. S. West, Brit. Freshw. Algae 211, figs. 85F-85H. 

 1904. 



Coenobia circular to ovoid, of 4-8-16-32-64-128-256 (generally 8- 

 16-32) cells that are normally compactly arranged in concentric rings. 

 Interior cells 4-6 sided, with straight sides. Inner half of marginal 

 cells similar to interior cells ; outer half produced into two short obtuse 

 processes ending in short spines, slightly to deeply emarginate between 

 the processes. Projections on outer face and their spines sometimes 

 greatly reduced. Wall smooth or granulate. (Facultative Planktont). 



Diam. cells 7.5-30 /*. Diam. 16-celled coenobia 40-100 /*. 



Balsam (rrr), Bear (1) (rrr), Bear (2) (rrr), Bear (3) (ss), Bear Trap 

 (rr), Beasley (rr), Beaver (rr), Beaverdam (ss), Big Butternut (rr), Birch 

 Island (rr), Blake (rr), Bloom (r), Boulder (rrr), Browns (rr), Camp (r), 

 Carroll (sss), Carson (rrr), Catherine (rr), Center (ss), Chetac (rr), Chetek 

 (rrr), Clear Crooked (rr), Cochrane (rrr), Crawling Stone (rr), Deer (r), Des 

 Moines (rr), Devils (1) (rr), Eagle (sss), East (rrr), Elizabeth (rrr), Fence 

 (rrr), Fishtrap (rr), Found (rr), Fowler (rrr), Geneva (rr), Granite (rr), 

 Grassy (rr), Green (2) (rrr), Grindstone (rr), Half Moon (rrr), Harris (rr), 

 High (rr), Hillman (rr), Hooker (rr), Horse (rrr), Horseshoe (1) (ss), 

 Kawaguesaga (r), Kegonsa (sss), Kitten (rr), Lac la Belle (rr), Lac Court 

 Oreilles (rr), Lac du Flambeau (r), Lindy (rr), Little Bass (2) (r), Little 

 Bear (sss), Little Butternut (rrr), Little Crooked (rr), Little Rice (2) (rr), 

 Little Wood (rrr), Long (2) (rr), Long (3) (rrr), Loveless (r), Lower Nash- 

 otah (rrr), Lower Nemahbin (rr), Lower Turtle (rr), Marl (rr), Mary (ss), 

 Mendota (ss), Monona (ss), Mud (1) (r), Mud (2) (r), Mudhen (rr), Muskal- 

 longe (rr), Nagawicka (rr), Nancy (sss), Nicaboyne (rrr), Oconomowoc (rr), 

 Old Taylors (rr), Owen (r), Paddock (rrr), Pewaukee (rr), Pine (2) (rrr), 

 Pokegama (1) (sss), Pokegama (2) (r), Pokegama (3) (rr), Poor Farm (rr), 

 Poplar (rr), Prairie (rrr), Rainbow (rr), Reserve (rrr), Rice (1) (rr), Round 

 (1) (sss), Round (2) (rr), St. Croix (rr), Sand (1) (rrr), Sand (3) (rrr), 

 Sand (4) (sss), Silver (2) (r), Spirit (rr), Star (rr), Streitor (rr), Taylor 

 (r), Tenderfoot (rrr), Tied Canoe (rrr), Turtle [North and South] (rr), Up- 



