| Dykes 1913; notes this is an Iris filifolia misidentified as I. Tingitana Baker gave the following description ;"The large lilac-flowered Irises with a bulbous rootstock fall into two well-marked groups, firstly Xiphion and xiphioides, well know and wisely cultivated in pre-Linnean times; and secondly, the less known, more recently described, and rarer Mediterranean types, filifolia, Fontanessii, and the present plant. The latter possess a distinct cylindrical tube to the perianth above the ovary, whilst in the former there is no tube between the ovary and the diverging segments of the lmb. The present plant was discovered long ago by Schousboe and Salzmann in the neighborhood on Tangiers, but has only lately been brought into cultivation. It was first imported by Geo. Maw, and has been flowered successfully by Messrs. Leichtlin and Elwes and Professor M. Foster. Our plate was drawn from a plant communicated by the latter, which he flowered in April, 1884. Besides the presence of the tube, it differs from I. Xiphion in the growing bulbs shooting in the spring and not in autumn, in the stouter leaves entirely hiding the stem by their clasping bases, and in the much larger blade of the outer segments of the perianth. Prof. Foster calls attention to a point which has hitherto escaped notice, that whilst in Xiphion, tingitana, and filifolia the petaloid style is pressed tightly down against the claw of the outer segments, in xiphioides it is so much arched that a large insect can obtain easy access to the anther without forcing its way. It is very likely that these new Mediterranean types will prove more difficult to keep alive and to flower than their older-known allies.The Tangiers plant figured as X. tingitanum in this work at plate 5981 is a form of X. flifolium, which I have called intermedium.
Description. Bulb ovoid, pointed; outer tunics thin, reddish-brown, with strongly-marked veins. Stem stout, terete, about two feet long, quite hidden by the bases of the clasping leaves. Produced stem-leaves six or seven, linear, falcate, the lowest a foot long, deeply channelled down the face, tapering to a point, pale glaucous green. Flowers two or three in a single terminal cluster; outer spathes-valves lanceolate, about four inches long, membranous at the margin and tip. Ovary cylindrical, one and a half or two inches long; pedicel short; perianth-tube cylindrical, as long as the ovary; limb bright lilac or purple; outer segments obovate unguiculate, three inches long, with a deflexed limb as long as the claw, with a bright yellow keel; segments lanceolate, concolorous, erect, as long as the outer. Styles with large deltoid erect plicate toothed appendages. Anther linear, much longer than the free filament."
| Dykes, The Genus Iris 218. tab. 44. 1913, Descnption. Rootstock , an ovate bulb, with slender, scarcely ribbed outer tunics. Leaves , 12 or more inches long, very slender and tapering, 5-7 in number, the uppermost being much reduced ; the leaves of non-flowering bulbs are much longer, 2 or more feet in length. Stem , about 12 or 18 inches high, bearing a single, usually 2-flowered head. Spathe valves, pointed, rigid, green, sharply keeled, the inner valve being slightly longer than the outer, 2½-3 in. in length. Pedicel , 1-1½ in., growing eventually to as much as 3 in. Ovary , an inch or slightly more in length, much rounded trigonal, with a groove running down each face. Tube , ½-1 in., slender. Falls , 2½ inches in length, the panduriform haft being longer than the orbicular blade. The colour is of a rich reddish purple with darker veins set off by an orange signal patch, which ends broadly on the blade, not narrowing to a point. There is also a slightly raised central orange ridge. Standards , distinctly obovate unguiculate with a blunt emarginate end. The colour is similar to that of the falls. Styles , broad, of the same colour. Crests , large, quadrate, with serrate upper edge. Stigma bilobed Filaments slightly longer than the anthers Anthers cream Pollen , yellow. Capsule , 2-2½ in. long, narrow, rounded trigonal, with deeply grooved sides. Seeds , small, wedge-shaped, wrinkled, of a rather yellowish brown, very numerous, as many as 236 having been counted in a single capsule.Observations.The name of this species is perhaps a little misleading, for although in some specimens, especially in the case of non-flowering bulbs, the leaves are very long, narrow and threadlike, yet in others they are distinctly stouter. This variability of the foliage has led to some confusion owing to the fact that a stout form was figured in the Botanical Magazine as Xiphion tingitanum (cf. synonymy). I. filifolia differs from I. tingitana in its broad, bluntly rounded standards and in its colour. It is perhaps one of the most striking of the Xiphium section. Its rich red-purple flowers are of a shade that is not found elsewhere. Another peculiarity is that the central orange patch is surrounded by a halo of blue. A microscopic examination reveals the fact that no blue pigment is present and that the blue colour is produced by a mixture of the orange and the red-purple cells, where the two colours run one into the other.This Iris does not seem to be any more difficult to cultivate than the other members of the group. See p. 210. Its leaves shoot in autumn and yet plants from Spain, at any rate, have remained untouched by twenty degrees of frost, when the foliage of I. tingitana has been severely crippled. It does not flower until June.