POLYMNIA, leaf cup 
Polymnia canadensis L. [S: incl. f. radiata (A. Gray) Fassett] 
(Wells, 1965), p. 1546 
Polymnia laevigata Beadle, p. 1547 
P. uvedalia (L.) L., bearsfoot, yellow flowered leaf cup [S: incl. 
var. densipilis S. F. Blake] (Wells, 1969), p. 1546 
PRENANTHES, rattlesnake root, white lettuce 
Prenanthes alba L., white lettuce, rattlesnake root, white 
snakeroot, p. 1648 
P. altissima L., rattlesnake Toot, tall white lettuce, p. 1648 
var. altissima, see excluded taxa 
var. cinnamomea Fern. 
P. aspera Michaux, rattlesnake root, rough white lettuce, p. 1648 
P. crepidinea Michaux, rattlesnake root, great white lettuce, 
p. 
P. racemosa Michaux, rattlesnake Toot, glaucous white lettuce, 
1646 
Ssp. racemosa 
PRIONOPSIS, goldenweed 
[S, G HAPLOPAPPUs] (see below) 
Prionopsis ciliatus (Nutt.) Nutt. [S, G: Haplopappus ciliatus (Nutt.) 
DC] (recent, as yet not fully published research has 
shown that the traditional genus Haplopappus is 
composed of diverse, unrelated elements; for example, 
Prionopsis is Closely related to, and perhaps congeneric 
rtman et al. (1987) and Lane et 
al. (1987) for brief discussions), p. 1500 
PYRRHOPAPPUS, false dandelion 
Pyrrhopappus carolinianus (Walter) DC 1646 
F: 8randiflorus (Nutt.) Nutt., see excluded as 
S: Steyermark ¢: Great Plains Flora M: Mohlenbrock 
