SMITH: ALGAE FROM THE LAKES OF WISCONSIN 473 
thaler is not typical since the pyrenoid is never outside of, but al- 
ways within, the chromatophore. 
Kirchneriella elongata sp. nov. 
Colonies of four, eight, sixteen, or many cells embedded in a 
copious homogeneous matrix. Cells cylindrical, rounded at ends 
spirally or irregularly twisted into a knot-like snarl. Chloroplast 
single, parietal, without (?) a pyrenoid. 
Colonies up to 1004 in diameter. Cells 25-15 uw long, 2.75- 
2.00 » wide 
PLATE 24, FIG. 7 
DISTRIBUTION: plankton, No Mans Lake; along shore, Plum 
Lake. 
This species approaches K. contorta (Schmidle) Bohlin, which 
I have collected from four Wisconsin lakes, but the cells are larger, 
some being twice as long as those of K. contorta, and there are 
usually more cells to the colony. 
SCHROEDERIA SETIGERA (Schréder) Lemm. 
Reinschiella setigera Schréder, Ber. Deutsch. Bot. Ges. 15: 489. 
pl. 25, f.4: 1897. 
Schroederia setigera Lemm. Hedwigia 37: 311. 1898. 
Raphidium setigerum W. & G. S. West, Trans. Yorkshire Nat. 
Union 25: 122. Igor. 
Ankistrodesmus setigerus G. S. West, Brit. Freshw. Algae 224. 
f.94F. 1904. 
PLATE 24, FIG. 8 
An organism found in the plankton of Devil’s Lake agrees very 
well with the original description of S. setigera, with one exception. 
Schréder and the Wests appear to be the only ones who have 
observed the living plant and neither mentioned the disc at the 
end of one of the prolonged apices. There is no doubt in my mind 
but that this structure was present in the cells they studied, but 
since it is practically invisible under a magnification of six 
hundred diameters or less, they probably overlooked it. 
An apparently closely related form is Ankistrodesmus nitzschi- 
oides G. S. West,* which has also been figured by Printz.t It differs 
* Jour. Linn. Soc. Bot. 38: 140. pl. 5, f. 18. 1907. 
T Ske. Vidensk. Kristiania, Math.-Naturvid. Kl. 1913°:97. pl. 7,f.217-220. I914. 
