1 889.] Botany. 1013 
them, but have seldom been rewarded, while I have found them almost 
exclusively in what I should term stagnant water. 
Docidium baculum (Breb.) D. By. Not common. 
Cosmarium bioculatum Breb, Not uncommon, 
Cosmarium conspersum Ralfs. Not common, 
Cosmarium meneghinii Breb. Not common. 
Cosmarium nitidum De Not, Not common. 
Cosmarium pulcherrimum Nord. Not common. 
Cosmarium undulatiim Corda. The only specimen found was 
partially undeveloped, but appears to be this species. 
Euastrum verrucosum (Ehrb.) Ralfs. A common form. 
Staurastrum gracile Ralfs, Not v 
Staurastrum polymorphum Breb. Not ^ 
Diatoms are, as in most places, common objects. Species of Epi- 
themia predominate. 
Cymbella gastroides Kutz. A large form, usually about 130 ji long. 
Navicula iridis Ehr., var. amphigomphus Ehr. 
Navicula major Kutz. Common. 
Naviculo. producta W. Sm, Not common. About 42 // long. 
Pleurosigma intermedium W. Sm. Rare. » 
Gomphonema clavatum Ehr. Rare. Length about 32 tu 
Gomphonema constrictum Ehrb. Common. Length 32-64 /x, 
Cocconeis pediculus Ehr. Common. Elliptical, 13-19 by 18-22 p.. 
Epithemia gibba Kutz. Not so common as the next. About 138 a long. 
Epithemia turgida (YAix.) Kutz. Very common. From 46-91 ji 
long, usually about 16 n wide. A very beautiful form. 
Synedra ulna (Nitsch) Ehr. Common. A very long variety of this 
was also found. 
Eragilaria harrisonii (W. Sm.) Grun. Only one frustule found. 
Melosira varians Ag. Quite common. Forming iq^ filaments from 
15-16 /.wide. 
Quite a number of other species were observed, of the genera 
JVitzschia, Ceratoneis, etc, but their identification remains doubtful. 
ZYGNEMACEtE. 
Zygnema cruciatum Ag. Common in some of the ponds. 
No attempt was made to collect the larger Algae. Great masses of 
what I took to be Spirogyra floated in some of the ponds. Cushions 
of Vaucheria were common on the wet banks,— H. J. Webber, Botan- 
tcal Laboratory, University of Nebraska. 
