122 
When looked for in 1887, they had disappeared. So far as known, 
this is the only locality within our limits where this species has 
been observed. 
1061. T, maritima, L. 
j , Marshy places from Woodlawn, southward, near the lake shore; not 
common. July — August. 
North of Chicago; rare. 
SCHETJCHZE&IA, L. 
1062. S. palustris, L. Scheuchzeria. 
Miller’s, Xnd., Bastin/ (B.) 
POTAMOGETON, Tourn. Pondweed. (Arranged by Prof. E. J. Hill.) 
1063. P. xiatans, L. 
Common in ponds, ditches and rivers. July — August. 
1064. p. fluitans, Roth. 
P. lonchites. Tuck. 
Aquatic, August, 1878, University of Chicago Herbarium. Chicago, 
Babcock. Desplaines river, near Desplaines, W. K. Higley. Deep 
ditches, South Chicago. July— -September. (B.) 
Frequent in the Calumet river, and usually growing, with very long 
stems, in deep water. 
1065. p e pulcher, Tuck. 
Rare, 1884 and 1885. June — August. (B.) 
As yet found in but one place ; in a slough by the roadside from 
Clarke to Pine Station, Ind. Perfect fruit found June 21st, but 
the upper leaves at that date were not full grown. 
1066. p. amplifolius, Tuck. 
Frequent in deep pools and ditches. August — September. (B. P.) 
Railroad ditches east of Englewood. South Chicago. Calumet 
river. Ponds in pine barrens, southeast. 
The stems are often branching , and floating leaves frequently absent. 
1067. P. heterophyllus, Schreb. 
P. gramineus, Fries. 
Desplaines river, near Riverside, W. K. Higley. July — September. 
Common in ditches and shallow ponds from Englewood eastward. 
A species exceedingly variable, especially in the shape and size of its 
floating leaves, and the number of its submersed leaves, these 
sometimes being few, but often very numerous, and differing con- 
siderably in size. Specimens collected at Pine Station, Ind., have 
the fruit plainly keeled, and with two parallel ridges rather fainter * 
than the keel, one on each side, becoming nearly or quite obsolete 
at the base of the fruit; submersed leaves short and numerous. 
