M. ringens, Bail., var. serrulata, n. var. — In size 
and form the same as the original type from Florida. Bailey 
describes it as „granular near the margins“, but not as 
serrated. This new variety has the margins distinctly 
‘ serrated. Found in large numbers in White Bear Lake, 
near Minneapolis, Minn., by Miss E. Butler. Diameter 
115—130 u by 125—145 u. 
M. furcata, Ag., var. simplex, n. var. — Cell 
equal in length and breadth, twolobed, end lobe exserted, 
its ‚divisions spreading, producing a wide, shallow sinus; 
lateral lobes usually simple, sometimes divided into two, 
narrow, linear divergent sections, furcate at apices. Length 
and breadth 140—150 u. 
A singularly variable species; of thirty-one specimens 
examined by Rev. H. D. Kitchel and myself, twenty were 
of normal form, as in the upper half of figures 6 and 7, 
no arms divided; five had all the lateral arms divided like 
the lower half of figures; one had two arms divided and 
one single; two had only one arm divided, and three had 
each two arms divided. 
All from pond near Winter Park, Florida. 
The second form mentioned, with all the lateral arms 
divided, is near the form described (Desmids United States, 
p. 111) as M. pseudofurcata, and needs further obser- 
vations. 
StaurastrumW olleanum, Butler, var. Missimense, 
n. var. — A large smooth and beautiful form, fully one- 
half larger than the typical plant from Minnesota. The 
arms are similarly constructed and arrauged, but, in gi 
ee with the body, are much longer, nearly equal in 
ength to the diameter of the body; apices notched, but 
tipped with several small spines. Diameter, including the 
arms, 100—125 u. 
. Grassy shores of lake at Kissimme, Florida, March, 
885. 
St. Tokopekaligense, n. sp. — Cell smooth, 
semicell in front view oval with gradiating arms; end 
view triangular, each angle drawn out into a smooth 
arm nearly as long as the diameter of the body; two 
similar arms on each side, all at nearly equal distances, 
and furcate at the apices. Diameter including arms, 75 u. 
This species occurs frequently in small coves of Lake 
Tokopekaliga, at Kissimme, Florida. It bears features in 
common with St. furcatum, Breb., but is about twice the 
