580 THE FLORA OF THE PRAIRIES. 
atum Linn.) ; the Indian plantain ( Cacalia tuberosa Nutt.), 
the tall verbena ( V. hastata Linn.), and the yucca-leaved 
rattlesnake master (Eryngium yuccefolium Michx.); all 
generally remarkable either for their large showy flowers, or 
the peculiar character of their foliage or habits. Finally the 
season closes with the later sunflowers and coreopses, some 
of which are of gigantic size, towering far above one’s head ; 
the purple- llomamd gaurias and the golden epilobiums. 
From the first springing up of the early flowers till the frosts 
of autumn end the floral season, the prairies are arrayed in 
bright and showy hues by a succession of species of larger 
and taller growth, each later set not only overtopping their 
predecessors, but the rapidly growing prairie grasses. Ever 
varied too are the prevailing colors. Here blue prevails, 
there white or purple, and again large tracks are golden, as 
everywhere a few prevailing forms give character to the veg- 
etation. Generally they are coarse, large plants, often res- 
inous, with thick, harsh leaves and large flowers, and nearly 
all are species never or rarely met with in the Atlantic 
States, and never as characteristic species of the eastern flora. 
The Composite and the Leguminose are preéminently the 
prevailing families, far more so indeed than at the eastward. 
Many of the species are in various ways remarkable, but 
none more so perhaps than the plant popularly known as the 
compass plant (Silphium laciniatum), whose large, thick, 
rigid, upright root-leaves, one to two and a half feet long, 
are reputed to uniformly present their edges north and soul) 
whence its name. Though they do aot thus invariably ar- 
range themselves, they generally stand in this direction, 
so uniformly in fact that they well serve as a convenient 
guide to the traveller in determining the points of the com- 
pass.* Another species of the same genus, called the cup 
nA dec NEUE bec onde dai Ti ME 
* Since the above was written an interesting paper on the Compass Plant was read 
by Dr. Thomas Hill at the Troy meeting of the American Association for the Advance- 
ment of Science, an abstract of (Vol. iv, p. 
495, October, 1870). Dr. Hill refers this polarity to the a the two sidan x the 
leaf being equally sensitive, and struggling for r equal 
