Showy Primrose (Hartmannia speciosa) is a large-flowered white primrose found on plains and prairies from North Texas to Missouri. The seed-capsules are narrowed at the base but are not stalked, and the calyx tube is longer than the capsule.
Rose Primrose (Hartmannia rosea) is a small-flowered primrose found in Southern and Southwestern Texas and Mexico. The flowers are small, an inch or more broad, with rounded deep-pink petals. The calyx tube is much shorter than the long-stalked capsule.
FLUTTER-MILL
Missouri Primrose. Flutter-Mill. Broad-Winged Evening-Primrose (Megapterium missouriense) clings to the side of a gravelly cliff or grows on rocky limestone hillsides from Missouri to Colorado and Texas. The flowers bloom in Texas in April and May, opening in the afternoon and closing the next morning. The plants grow in low clumps about a foot high. Numerous flowers are borne on the stem along with the slender leaves. Four broad yellow petals make up the cup-shaped portion of the flower above the slender calyx-tube, which is 4-6 in. long. The seed-capsules at the base of the flower develop four broad papery wings and reach at maturity a width of 3 in. These broad wings are responsible for the scientific name of the plant. The capsules are easily blown about by the wind, and the seeds are widely scattered.
The evening-primroses usually produce large, thready masses of pollen. Every child is initiated into a buttercup fraternity at some period in his life by being invited to smell of the flower and having his nose smeared with the profuse pollen.
SQUARE-BUD PRIMROSE
Square-Bud Primrose. Day Primrose. Creamcups (Meriolix spinulosa) has yellow cup-shaped flowers which last only twenty-four hours but which are open during the day. It may readily be distinguished from other evening-primroses by the slender woody stems which soon become reddish or straw-colored. The stems grow 1-1½ ft. high with clusters of flowers at the top. The flowers are nearly two inches broad and have four petals. The short, broad sepals are winged on the back and make the buds appear square and pointed.
Another distinguishing feature is the disk-shaped stigma which is sometimes yellow and sometimes black or dark brown. In the evening-primroses previously mentioned, the stigma is divided into four narrow lobes. The plants grow on gravelly hillsides from Arkansas to Mexico. The slender capsules are over an inch long. Several other day primroses are found in the state. They are all sometimes grouped with the œnotheras.