r 



GROUP IV. PHANEROGAMIA : ANGIOSPERMiE : MONOCOTYLEDOXES. 569 



Fam. 2. iRiDioiDEiE : flowers mostly actinomorpbic, forming many-flowered 

 inflorescences of various form with spathes, each of which invests more than one 

 flower : stem bulbous or rhizomatous. 



This large family includes several sub-families, of which the following are 

 the more important : — 



Sub-fam. Iridiiice : perianth-tube short or absent ; the capsule is not en- 

 closed by the spatbe ; the styles are petaloid, with the stigma on the under 

 surface. Iris, the Flag, is the principal genus. The species of this very large 

 genus may be divided into two groups based upon the bulbous or the rhizoma- 

 tous character of the stem. The most familiar of the bulbous Irises are, I. 

 xiphioidei (or Xiphion latifoHum, or Iris anglica) the so-called English Iris ; 

 I. Xiphium {Xiphion vulgare) the Spanish Iris ; I. reticulata, persica, and Histrio. 

 The rhizomatous Irises are classified according to the presence or absence of 

 hairs (beard) on the perianth-segments : thus, — 



Sect. Hexapogon : all the perianth-segments bearded along the upper surface 

 of the midrib of the claw : e.g. I. longiscapa and falcifolia. 



Sect. Pogoniris : only the three outer perianth-segments bearded on the 

 midrib of the claw ; e.g. I. Jlorfntina, gerinanica, pallida, pumila. 



Sect. Oncocvclus : the three outer perianth-segments bearded on both claw 

 and limb : e.g. I. susiana, iberica. 



Sect. Apogon : perianth-segments beardless : e.g. 1. graminea and siherica 

 with linear leaves ; I. Pseiidacorus, ochroleuca, foetidissima, etc., with ensiform 

 leaves. I. Paeudacorus (Yellow Flag) and foetidissima are British. 



Sub-fam. Tigridiiioi : perianth-tube absent; styles branched with an apical 

 stigma ; the inner whorl of perianth-segments is smaller than the outer ; sta- 

 mens monadelphous : bulbous plants. Tigridia Pavoida is the Tiger Flower. 



Sub-fam. Sisyrinchinoi : perianth-tube short ; styles unbranched, nearly 

 cylindrical, alternate with the stamens (not opposite as in Iris) : stamens free, 

 or connate at the base : rhizomatous plants. 



Here belong the genera Libertia (with free stamens) and Sisyrinchium 

 (with basally connate stamens), having actinomophic flowers; S. {Berinudiaiia) 

 august i folium, Blue-eyed Grass, occurs in Galway. 



Sub-fam. Aristince : perianth-tube elongated ; capsule enclosed by the spathe ; 

 stamens monadelphous (Patersonia) or free (Aristea) ; generally rhizomatous. 



Fam. 3. Ixioide^ : the flowers, which are frequently zygomorphic, are each 

 invested by a spathe : stem, usually a corm. 



In the sub-fam. Ixiece, the zygomorphism of the flower is but slightly 

 marked : Schizostylis is rhizomatous, whilst the other genera (Ixia, Geisso- 

 rhiza, etc.) are bulbous. 



In the Gladiolae, the zygomorphism of the flower is well-marked, but the 

 flower may be either straight and erect {e.g. Tritonia, Montbretia, Sparaxis), or 

 curved {e.g. Gladiolus). Gladiolus illyricus (communu), the lesser Gladiolas 

 or Corn-Flag occurs iu England. 



In the Watsonieoi (Watsouia, Lapeyrousia, Freesia), the styles are 2- 

 branched. 



