This section is from the book "An Illustrated Flora Of The Northern United States, Canada And The British Possessions Vol2", by Nathaniel Lord Britton, Addison Brown. Also available from Amazon: An Illustrated Flora of the Northern United States, Canada and the British Possessions. 3 Volume Set..
[Salpingia Raimann, in Engler & Prantl, Nat. Pfl. Fam. 3: Abt. 7, 217. 1893. Not Salpingo DC]
Perennial caulescent herbs or shrubby plants with much branched or tufted stems. Leaves alternate, entire or toothed. Flowers perfect, yellow, axillary. Calyx-tube slender, narrowly funnelform, longer than the ovary; calyx-segments narrow, the tips free in the bud. Petals 4, spreading. Stamens 8, equal in length; filaments filiform; anthers linear. Ovary 4-celled, elongated; united styles filiform; stigma disk-like, entire. Capsules elongated, narrowed at the base, more or less curved. Seeds sometimes tuberculate. [Anagram of Salpingia.]
Canescent or appressed-pubescent, low; leaves narrow.
Hirsute-pubescent or tomentose; leaves broad.
Oenothera lavendulaefolia T. & G. Fl. N. A. 1: 501. 1840. Galpinsia lavendulaefolia Small, Fl. SE. U. S. 845. 1903.
Somewhat woody, canescent, much branched, the branches decumbent or ascending, slender, 6'-15' long. Leaves linear-oblong or lanceolate, acutish at the apex, sessile, 6"-2' long, 1 1/2"-2" wide, entire or slightly repand-denticulate; flowers axillary, yellow, 1'-2' broad; calyx-lobes lanceolate to linear-lanceolate, acuminate, reflexed-spreading, the tube dilated above, many times longer than the ovary; petals rhombic-obovate; stigma discoid; capsule nearly sessile, narrowly cylindric, canescent, 6"-12" long, 1"-2" thick.
Galpinsia interior Small, Fl. SE. U. S. 845. 1903.
Somewhat woody, hirsute-pubescent, or tomentose, branched, 1° high or less, erect or ascending. Leaves oblong to oblong-lanceolate, entire, or nearly so, acute or obtuse at the apex, sessile by a somewhat clasping base, about 1' long; calyx more or less hirsute, its lobes lanceolate, acuminate, s"-8" long; petals 1/2'-1' long; capsules hirsute, 7"-10" long.
On plains and stony hills, Nebraska and Kansas to Texas. June-Aug.