Smith—Phytoplankton of the Muskoka Region. 
337 
QUADRIGULA Printz 1915 
Quadrigula Pfitzeri (Schrpder) G. M. Smith. 
Basil (rr), Big Dudley (sss), Black (1) (rrr), Black (2) (rr), Brush 
(rr), Burned Rock (rr), Butterfly (sss), Cornell (rrr), Corner (rr), 
Gull (1) (rr), Henshaw (rrr), Lake of Bays (rr), Little Dudley (rrr), 
Long (2) (rr), Marion (rrr), Mill (rr), Muldrew (rrr), Muskoka (rr), 
Nine Mile (rrr), Otter (rrr), Round (2) (rr), Rowley (rrr), Silver (1) 
(rrr), St. Mary (r), Thompson (rrr), Vernon (r), White (rr). 
ELAKTOTHRIX Wille 1898 
Elaktothrix gelatinosa Wille 
Black (1) (rrr), Clear (1) (rrr), Hamer (rrr), Leech (rr), Long (1) 
(rrr), Mill (rr), Muskoka (rrr), Otter (rr), Strange (rr), Vernon (rrr). 
KIRCHNERIELLA Sehmidle 1893 
Kirchneriella lunaris (Kirchner) Mobius 
Basil (r), Big Dudley (rrr), Brush (rrr), Burned Rock (rrr), Butterfly 
(r), Echo (rrr), Gull (1) (rrr), Gull (2) (rrr), Hamer (rr), Harbon 
(rrr), Henshaw (rr), Leech (rrr), Long (1) (rrr), Long (2) (rrr), Loon 
(rr), Mill (r), Muldrew (rrr), Muskoka (rr), Nine Mile (rrr), Otter (r), 
Pine (rrr), Rowley (rr), St. Mary (rr), Silver (1) (rr), Thompson (rrr), 
Vernon (ss). 
var. irregularis G. M. Smith 
Silver (1) (rrr). 
Kirchneriella obesa (W. West) Sehmidle 
Basil (rrr), Black (1) (rrr), Brush (rrr), Vernon (rrr). 
Kirchneriella arcuata sp. nov. PI. VIII, figs. 1-3. 
Cells with apices somewhat attenuated to a rounded apex, ar¬ 
cuate, lying some distance from one another within the homo¬ 
geneous gelatinous colonial envelope. Colonies generally four- 
celled, rarely with more than sixteen cells. Cellular arrangement 
within the colony indefinite. Chloroplast on convex side of cells, 
without a pyrenoid, hyaline spot on concave side of cell conspic¬ 
uous. 
Cells 2.S-5.3 p broad, 8-17.5 p long. 
Big Dudley (s), Muskoka (rrr). Silver (1) (rrr). 
The species is distinguished by the cell shape and the shape 
of the chloroplast as well as by the small number and arrange¬ 
ment of the cells within the colonial envelope. 
22—S. A. L. 
