| Dykes, The Genus Iris tab. 23. 1913, Description. Rootstock , a thick rhizome covered with the fibrous remains of old leaves. Leaves , ensiform, green, slightly glaucous and usually tinged with purple at the base, 1-2 ft. long and ½-1 in. broad. Stem , stout, solid, deeply forked, bearing several heads of flowers, of which those on the first lateral branch rise as high as those on the main stem. A reduced leaf is attached at each bifurcation. Spathe valves, narrow, acuminate, unequal, 1t-2 in. long, the outer valve being the shorter, green or flushed with purple or slightly scarious, 2-3-flowered. Pedicel, 1-1½ in. long. Ovary , acutely trigonal, green or flushed with purple. Tube , ¼--i in., shorter than the ovary, and scarcely separated from it by any construction. Falls . The orbicular or more usually heart-shaped blade narrows abruptly to the short wedge shaped haft. The latter is veined with purple on a yellowish white ground. The white ground, veined with purple, is visible for a short distance on the blade, which then becomes a uniform purple with inconspicuous darker veins. The exact shade of purple is very variable ; it is usually a blue purple but has sometimes a distinctly red tinge. Standards . Variable in shape but not more than ½-¾ inch long. The most usual form is broad at the base, narrowing abruptly to a long fine point. Less frequently the width increases a second time before narrowing to a short point (see Fig. 12). Styles , short, oblong, about 1 in. long, whitish with purple keel. Crests , overlapping, subquadrate, with coarsely serrate edges. Stigma , a rounded, triangular tongue. Filaments , purple or yellow stained with purple. Anthers , purple. Pollen , cream. Capsule , much inflated, trigonal with grooved sides, scarcely twice as long as broad. The seeds soon become detached and rattle m the capsules. Seeds , light brown, glossy, with conspicuous raphe down one side (see Plate XLVIII, Fig. 15.ObservationsIt is not at present possible to separate and define the various forms of this Iris that are already known to us. It was first found by Pallas in Siberia and extends to the extreme north-eastern corner of Asia. From there it passes into Alaska and finally reappears again on the east coast of Canada and Maine. Under the names of setosa, setosa canadensis, Hookeri and tridentata, I have found growing in gardens at least six forms of this Iris. What is more curious is that each form when self-fertilized comes practically true from seed. The variations are in stature, in the green or purple base to the leaves, in the green or purple flushed spathes and ovary, in the foliage and in the shape of the segments. The various forms, when grown side by side, are obviously distinct and yet equally obviously unworthy each of a specific name. The features that are common to all are the minute, bristle-like standards from which the species obtained its name, the large heart-shaped falls, the curious way in which the topmost lateral branch rises as high as the main stem, the inflated capsules with thin membranous walls and the characteristic seeds (see Plate XLVII I, Fig. 15), which are totally unlike those of any other species.Until seeds have been obtained from the various localities and plants raised and grown under identical conditions, it seems unwise to attempt to separate the various forms, for the differences that are apparent in the living plants are· usually quite invisible in the ordinary herbarium specimens. I have at last succeeded in obtaining seeds both from the east coast of America and from Eastern Asia but the plants raised from them show no difference except in colour and size. The Asiatic examples are of a reddish purple and the stems 18-24 in. high, while those from the coast of Maine have a 10-12 in. stem and blue-purple flowers.I. setosa varies in height from about a foot to slightly over two feet. By some curious confusion, there is now in cultivation a dwarf form under the name of I. Douglasiana pygmaea. It is very floriferous and a desirable garden plant. It is possible, and indeed probable, that this may be the Labrador or Alaskan form 1, for all the Labrador specimens that I have seen were of this size and appearance and so too apparently were the Alaskan plants described by Miss Eastwood as I. arctica. On the other hand, the tallest form that I possess was sent to me from Russia and said to be from Kamchatka. I am afraid, however, that especially in the case of this Iris, I am very unwilling to accept as authentic any supposed local form that does not come to me direct from the locality in question. The reason is that I. setosa with its pointed tongue-like stigma is certainly self-fertile. Every flower produces a capsule of seed, which when ripe is very easily scattered broadcast. The seeds germinate as readily and may thus oust the original occupants of the spot on which they fall. Probably some such cause as this accounts for the name of I. Douglasiana pygmaea attached to what is undoubtedly a form of I. setosa.Cultivation presents no difficulty in any soil not too strongly impregnated with lime. The plants enjoy abundant moisture during the growing season but flower well, though with smaller blooms, even in poor, dry sand. The species is very easily raised from seed and the young plants can generally be relied upon to flower before they are fifteen months old. No white-flowered form appears to be in cultivation, but a specimen was found by Dr Takeda in 1909 on the Tomoshiri Promontory, near Nemuro, Yezo.