Smith—Phytoplankton of the Muskoka Region. 
361 
SPHAEROZOSMA Corda 1834 
Sphaerozosma granulatum Roy & Biss. 
Basil (rr), Round (2) (rrr), Silver (1) (r). 
Sphaerozosma excavatum Ralfs. 
Mill (rrr), Strange (rrr). 
ONYCHONEMA Wallieh 1860 
Onychonema laeve var. micracanthum Nords. 
Round (2) (rr). 
A form with the spines about half the size that Nordstedt gives 
was noted in Round Lake in Wood Township (PL XIII, fig. 16). 
var. latum W. & G. S. West 
Brush (rrr). 
SPONDYLOSIUM Brebisson 1844 
Spondylosium planum (Wolle) W. & G. S. West 
Burned Rock (r), Joseph (rrr), Long (2) (rr), Muskoka (rr), St. Mary 
(rrr). 
Spondylosium pulchrum (Bailey) Arch. 
Gull (1) (rr), Otter (rrr), Pennsylvania (rrr), Silver (1) (rrr). 
HYALOTHECA Ehrenberg 1841 
Hyalotheca mucosa (Dillwyn) Ehr. 
Black (2) (rrr), Brush (rr), Cornell (rrr), Little Dudley (rr), Long 
(1) (rrr), Loon (rrr), Marion (rrr), Mill (rr), Mud (rrr), Strange (rrr). 
DESMIDIUM C. A. Agardh 1824 
Desmidium aequale W. & G. S. West 
Burned rock (rrr). 
Desmidium cylindricum Grev. 
Pennsylvania (rrr). 
