354 Wisconsin Academy of Sciences, Arts, and Letters. 
Length (without processes) 25-28 /a, (with processes) 32-50 /a; 
breadth (without processes) 16-20 /a, (with processes) 56-75 
breadth isthmus 6-8 /a. 
Big Dudley (rrr), Gull (1) (rr), Long (2) (rrr), Otter (sss), Round 
(2) (rr), iRowley (s). 
var. obesran var. nov. PL XII, figs. 3-5. 
Semicells stouter and with the processes sub-parallel. Processes 
slightly upturned at their apices. 
Length (without processes) 35-40 /a, (with processes) 47-60 /a; 
breadth (without processes) 25 /a, (with processes) 60-68 /a; 
breadth isthmus 10-12 /a. 
Burned Rock (r), Echo (rrr), Gull (1) (r), Miuldrew (rrr), Silver 
(1) (sss). 
Statjrastrum pseudosebaldi Wille 
Clear (1) (rrr). 
Statjrastrum vestitum Rails 
Basil (rrr), Pennsylvania (rrr). 
var. subanatinum W. & G. S. West 
'Clear (2) (r), Long (2) (rrr). 
Staurastrum anatinum Cooke & Wills 
Butterfly (sss), Clear (2) (rr), Harbon (ss), Henshaw (rrr), Long (1) 
(rrr), Otter (rrr), Thompson (rrr). 
var. longibrachiatum W. & G. S. West 
Echo (r), Gull (1) (rr), Leech (rrr), Loon (rrr), Muskoka (sss), 
Nine Mile (r), Round (2) (rr), Rowley (sss), Silver (1) (sss), Vernon 
(sss). 
var. curtrnn var. nov. PI. XII, figs. 6, 7. 
Body of cell smooth below the apex. Processes short, parallel, 
not divergent. 
Length 30 /a; breadth (without processes) 25 /a, (with processes) 
68-75 n ; breadth isthmus 11 /a. 
Big Dudley (rr), Brush (rr), Burned Rock (r). 
This variety shows considerable resemblance to the variety 
longibrachiatum, but differs in the nature of the processes which 
are shorter and not divergent. The length of the cells is also con¬ 
siderably less than that of other varieties of the species. 
