Best I can do is to quote what Alan Edwards wrote about the plant when it was awarded a Preliminary Commendation by the Joint Rock Committee in 1993.
I am not quoting the report verbatim - I’m missing out any extra details that do not pertain to the actual plant.
"This little gem came to me from the garden of my good friend Lyn Bezzant at Port of Menteith where it has multiplied abundantly for many years. Lyn tells me that this distinct and vigorous form of the familiar species came originally from the garden of Willie Buchanan, the celebrated Scottish plantsman who was a founder member of the SRGC and who died in 1963. Origin of the plant Is obscure because Willie was no scribe; his encyclopaedic knowledge of the plants and their associations in his half-acre garden at Bearsden died with him. We know he maintained a large circle of botanist friends world-wide with whom he exchanged plants and seeds, so possibly this form was found in the wilds of Iberia and reached Willie via a correspondent.
So far ‘Douglasbank’ seems to relish life in the deep south as much as it does north of the border. I grow it in a peat bed and also in a raised bed among dwarf rhododendrons. I see no reason why it should not also make an ideal pot subject, like other forms of N/ minor and N. asturiensis. I suggest also that, like these, it thrives best in a moist, neutral soil, ideally enriched with leaf mould to which a high-potash fertiliser is added for good measure as soon as growth appears. Given such conditions a few bulbs will quickly form generous clumps and produce good capsules of seed in most years.
Among other small narcissus in late February ‘Douglasbank’ is instantly recognisable due to its emergent flower stem being held at an angle of 45-60 degrees, with colour already showing and the pedicel and developing bud already twice the length of the 5cm stem. For a day or so the bud tip may touch the ground, but growth progresses rapidly and after another short interval it attains the following dimensions and characteristics:
Leaves: glaucous, 3 -5 per bulb, erect, 5mm wide, 10 -12 cm long, slightly twisted. Stem: oval, striated,12 – 13 cm long, held vertically or inclined at 15 degrees at flowering. Pedicel: 1.5 – 2 cm, held at right angles to the stem. Tube: 1.5cm, yellow with green shading towards the base, 9mm wide with a papery brown spathe extending to half the length of the tube. Flowers: solitary, horizontal or just below, c.4cm diameter. Perianth segments: slightly twisted, slightly drooping, yellow with a pale base, 15mm long, 9mm wide , tips pointed and whitish, imbricate at base only. Corona: a shade deeper yellow, 2cm long, notably waisted (8mm), much expanded and frilled at the mouth into six lobes ( 1.5cm). Anthers: yellow, uniform length, extending to half the length of the corona. Style: whitish, extending well beyond anthers but entirely within the corona.
John Blanchard considers the award material to be distinct from the usual forms of N. minor encountered in the trade and therefore the name ‘Douglasbank’ linked to the above details has duly been accepted by the RH Daffodil Registrar. It is indeed surprising that such a cultivar should have been so long in cultivation without receiving a reward. Lyn Bezzant suggested the name Douglasbank because the name William Buchanan was already in use."
I would add that it does not flower as early as February here in Aberdeen - but it is a distinct little thing, nonetheless.