58 
TANACETUM (S, G: incl. CHRYSANTHEMUM) 
(Heywood, 1959a, b; Heywood and Humphries, 1977) 
*Tanacetum parthenium (L.) Schultz-Bip., feverfew [S, G: 
Chrysanthemum parthenium L.] (Heywood, 1959a, b; 
Heywood and Humphries, 1977), p. 1605 
+T. vulgare L., tansy, common tansy, golden buttons, p. 1605 
f. crispum (L.) Hayek 
f. vulgare 
TARAXACUM, dandelion 
*Taraxacum erythrospermum Andrz. ex Besser, red-seeded 
dandelion [G, M: T. laevigatum (Willd.) DC.] (there is 
widespread disagreement on the correct name for this 
taxon; pending critical examination of type specimens, 
the traditional nomenclature for this aggregate of 
largely apomictic races is followed here, which also 
agrees with current usage in most European manuals), 
p. 1634 
¢T. officinale Weber, common dandelion (the name T. officinale 
has recently been lectotypified (Richards, 1985) based 
on a Scandinavian endemic that is only distantly related 
to the widespread, weedy species to which our plants 
are referrable; unfortunately it is unclear which of the 
nearly 50 names placed in sect. Ruderalia (Kirschner 
and Stépanek, 1987) should be used for the introduced, 
North American plants, and we have continued to use 
the traditional nomenclature until further study clarifies 
the situation), p. 1635 
THELESPERMA 
T. filif ambiguum A. Gray, see excluded taxa 
oe (Hook.) A. Gray [S: T. trifidum (Poiret) Britton] 
__(Shinners, 1950a; Turner, 1959), p. 1580 
var. filifolium 
*T. megapotamicum (Sprengel) Kuntze, p. 1580 
S: Steyermark G: Great Plains Flora M: Mohlenbrock 
