THE AMERICAN BOTANIST 99 



tain tops, in deserts and in the Arctic regions — plants usually 

 display an abundance of flowers and these of a size quite out 

 of proportion to the vegetative parts. On the Chicago plain a 

 similar condition prevails. Throughout the growing season, 

 the region is more thickly spread with bloom than any other 

 within a radius of many miles. Great masses of a single color 

 stretch away to the horizon and the transient visitor might 

 jump to the conclusion that only a few species inhabit the 

 region, but this only illustrates the fact that each species has 

 its particular season of bloom. Wave after wave of color 

 sweeps over the spot as the summer waxes and wanes, each 

 spending itself after a few days or weeks but leaving behind 

 it little eddies and splashes of color that flash in out-of-the- 

 way places for some time longer. Occasionally two species 

 come into bloom at the same time and then the surface takes 

 on a mottled appearance as one group vies with another. Not 

 all the characteristically prairie species, however, are gre- 

 garious enough to produce such displays. Many seem to pre- 

 fer existence in isolated clumps, and it is the chance of en- 

 countering these that lends zest to the exploration of the 

 region. 



With the exception of grasses and sedges, the monocotyle- 

 dons are not abundant in the area. Only three species are 

 plentiful enough to give a note of color to the scene. These 

 are the spiderwort, star grass and blue-eyed grass. The least 

 specialized dicotyledons are also few in numbers. Fully one 

 third of the species represented belong to the dominant group 

 of composites while a still greater proportion of individuals 

 are of this alliance. A list of all the plants growing in the 

 region would be too long for inclusion here, but a list of the 

 more conspicuous is given. Riding across the region, these 

 are the ones likely to be seen and recognized. It is only when 

 explorations are conducted on foot that less conspicuous spe- 

 cies appear. 



