123 
179. S. nanum, Wolle, p. 138, Pl. XLIV.—Our specimens 
granulose punctate. Pushaw stream. Oct., 1891. 
180. S. Sedaldi, var. QUARTERNUM, n. var. Distinguished 
from the type by absence of spines; smaller size (5 4), broader 
appearance and quadrangular end view. Fig. 16 side view; fig. 
17 end view. Pushaw stream. Oct., 1890. F. L. Harvey. 
181. S. ELustephanum (Ehrb.), Ralfs, p. 147, Pl. XLVUL— 
The peculiar form shown at fig. 7 is doubtfully referred to the 
above species. It was 55 4 broad including the spines, and en- 
closed in a hyaline sheath with a dentate border which was over 
75d. The cytoplasm of the included form was dark green, 
and the half cells not symmetrical, the smaller half cell having 
only three processes. Only one specimen observed. Sketched 
for the writer by F. P. Briggs. Pushaw stream. Oct., 1890. 
182. S. arctiscon, Ehrb., var. CRENULATUM, n. var.—Some- 
what smaller than type, half cells more rounded, processes thick- 
er and with crenulate margins (fig. 18). Pushaw stream. Oct., 
1890. F. L. Harvey. 
Family XVI.—Conjugate. 
183. SPIROGYRA AQUALIS, n. sp. 
Diameter of vegetative filaments quite constant, about 45 /; 
5-10 times longer than broad ; spiral single (rarely two), mak- 
Ing usually 5 to 10 turns, though 6, 7, 8 and 9 were occasionally 
observed ; end inlaid, chlorophyl of the bands coarsely granular 
with about six largenucleitoeach turn. Sporiferous cells not swol- 
ita same width and length as the vegetative, and often curved ; 
Conjugation lateral, zygospores elliptical or spherical ; 40 x 40 #, 
45X45 yu, 45x75 “and 45 x 105 “ were the dimensions ob- 
Stved. The spores were as wide as the filaments, extending to 
the walls, which were not inflated ; scalariform conjugation not 
observed ; lateral conjugation quite abundant; plant in mass, 
sfass green and slippery, spores somewhat darker green ; doubie 
pret Single spirals were observed in contiguous cells of the same 
Ment. 
_ Abundant in pools in a swamp on the college campus. Oct., 
1891. Collected by F. L. Harvey. (Figs. 19-21). ae 
The replicate ends of the cells, the single spiral, and the 
‘mooth membrane of the spores, puts the plant into the S. tenuts- 
“a section of Wolle. The only plant mentioned at all related 
