Date of this Version
The American Naturalist (June 1880) 14(6): 417-421.
The plant under consideration is a common herbaceous perennial of the prairies and great plains of North America. In the latter part of April and during the month of May it produces flowers with bright yellow salver-shaped (hypocraterimorphous) corollas, whose tubes are about thirty mm. (one and one-fifth inch) long, and from two to three mm. in diameter. About the first of June, in central Iowa, these large flowers suddenly disappear, and from this time forward until the autumn frosts, they produce only small cleistogamous flowers. The corolla lobes of the latter cohere somewhat, and remain closed, and in this condition the total length of the corolla is from five to seven mm., the tube itself being no more than three to five mm. long. Both kinds of flowers produce seeds, and I have not observed any difference in their relative fertility, although there are actually at least ten times as many seeds produced during the season by the small flowers as by the large ones, for the reason, however, that there are many more of the former flowers than of the latter. Of the small flowers I will have somewhat to say at another time ; what I wish particularly to notice at this time is the relative position of stamens and stigma in the large early flowers.