276 
PONTEDERIA, pickerel weed 
Pontederia cordata L., pickerel weed, p. 40 
var. cordata [S: incl. f. latifolia (Farw.) House] (Lowden, 
1973) 
ZOSTERELLA (see HETERANTHERA) 
POTAMOGETONACEAE, pondweed family 
[S: NAJADACEAE] 
POTAMOGETON, pondweed 
Potamogeton amplifolius Tuckerman, largeleaf pondweed, p. 54 
+P. crispus L., curly muckweed, beginner’s pondweed, p. 52 
P. diversifolius Raf., waterthread pondweed, p. 54 
P. epihydrus Raf., ribbonleaf pondweed, p. 54 
var. ramosus (Peck) House [S: var. nuttallii (Cham. & 
Schldl.) Fern.; G: P. epihydrus] (Voss, 1972) 
P. x faxonii Morong, see named hybrids 
P. foliosus Raf., leafy pondweed, p. 52 
var. foliosus [S: incl. var. macellus Fern.) (Haynes, 1974) 
P. illinoensis Morong, Illinois pondweed, p. 55 
P. nodosus Poiret, longleaf pondweed, p. 55 
P. pectinatus L., fennel-leaved pondweed, sago pondweed, 
52 
p. 
P. pulcher Tuckerman, spotted pondweed, p. 55 
P. pusillus L., baby pondweed, p. 54 
var. pusillus 
S: Steyermark G: Great Plains Flora M: Mohlenbrock 
