STRUCTURE OP THE FORMATION 75 



number depending largely upon the location of the quadrat 

 within the Coreopsis patch. During June these masses of 

 yellow-rayed bloomers contrast sharply with the other mostly 

 white and blue flowers. The plants are perennial ; root prop- 

 agation obtains, hence the patches. Brauneria pallida is a 

 xerophyte with thick, black roots and rigid stems and leaves. 

 It invariably occurs on high prairies and ridges, where it 

 averages 25-30 individuals to the quadrat. Brauneria begins 

 blossoming during the first week of June and continues for 

 over a month. The spreading rose rays surround a cone of 

 brown and altogether produce a pretty effect. These flowers 

 are easily recognized at a distance of fifty meters. Acerates 

 viridi flora linearis and A. viridiflora ivesii are two typical 

 xerophytes of Great ridge. Both are perennial, solitary 

 plants, recognized only with difficulty in the floral covering 

 on account of the uniform color of flowers and leaves. Their 

 follicles containing comose seeds mature September 1. 

 Anemone cylindrica is neither frequent nor abundant, oc- 

 curring only at a few stations on Great ridge. It is a per- 

 ennial xerophyte. The few greenish-white, unattractive 

 flowers appear during the first or second week of June, last- 

 ing for a few days only. The ragged heads are common on the 

 prairies during July and August, the woolly achenes of which 

 are carried by gophers to their burrows. 



The tuberous-rooted Indian plantain, Mesadenia tuberosa, 

 is a rare plant in the low prairies. The stems are at least one 

 meter high and terminate with a showy, white corymb easily 

 distinguishable for 200 meters. Verbena stricta occurs oc- 

 casionally in low prairies and meadows. Its hairy, rigid 

 stems, bearing terminal racemes of blue flowers, grow from 

 perennial roots. The curved salver-form corolla includes the 

 didynamous stamens which exceed the style (herkogamy). 

 When the insect, usually one of the Hymenoptera, is securing 

 the nectar, he is quite sure to leave pollen of some other ver- 

 vain flowers upon the stigma, allogamy resulting. It is to be 

 noted that Y. stricta is rather abundant in a pasture of two 



