The old Cyclopedia of American Horticulture (1904) gives the parentage of Gladiolus x gandavensis as G. psittacinus x G. cardinalis; an alternative parentage is also given: G. psittacinus x G. oppositiflorus. The colors are given as "bright shades of red and red-yellow variously streaked and blotched". Gladiolus primulinus and its hybrids are not even mentioned in this edition. In the 1925 edition of the same work, Gladiolus primulinus is described as having been discovered in 1887 and first flowered in 1890; the color is described as being "clear primrose yellow throughout". The "throughout" I think is as significant as the "clear primrose yellow", since the old gandavensis sorts were described as streaked and blotched. The second edition discusses nearly forty species of Gladiolus, but neither edition mentions the name Gladiolus dalenii. I suspect that the old gandavensis hybrids were very different from the the primulinus hybrids: the primulinus hybrids created a sensation in the glad world around the time of the First World War, and were widely praised for their graceful form both of bloom and overall inflorescence and their then novel colors. I've seen old paintings and old photos of old garden glads and "graceful" is not the word which comes to mind. Clunky is more like it. The primulinus hybrids are nothing like that. I have always thought that these pale yellow "hooded" "primulinus" hybrids are among the loveliest of hybrid glads. In other words, I think gandavensis hybrids and primulinus hybrids are very distinct groups - or maybe I should say were at one time very distinct, because both were long ago swallowed up in the main mass of glad hybrids. Several nurseries are selling something they are calling Galdiolus x gandavensis, but all of the ones I've seen have been primulinus hybrids (or should I be saying daleni hybrids? Old habits die hard.). Do any true Gladiolus x gandavensis hybrids survive? I don't know, but they had their hayday over 150 years ago, and it seems unlikely. And since glads were continually and enthusiastically re-hybridized during the nineteenth century, identifying such a thing with certainty strikes me as really daunting. Jim McKenney Montgomery County, Maryland, USA, USDA zone 7, where I'm glad to have glads in the garden.