IRIDACEAE 63 



Family 25. DIOSCOREACEAE Lindl. 



Twining vines with large tuberous roots, petioled, cordate-ribbed and 



reticulate-veined leaves, and inconspicuous, greenish, dioecious, 6-androus 



flowers. Stamens 3 or 6. Ovary inferior, 3-celled, 3-6-ovuled. Stigmas 



and styles three each. 



1. DIOSCOREA L. 



Flowers in axillary racemes or panicles. Capsule 3-winged, loculicid- 

 ally 3-valved. 



1. D. villosa L. Wild Yam. Leaves alternate, cordate-acuminate 

 slightly downy beneatli: staminate flowers in drooping panicles, the 

 fertile in drooping racemes: capsules strongly winged. — In thickets 

 throughout. Well distributed, but not common. May- July. 



Family 26. IRIDACEAE Lindl. 

 Perennial herbs with equitant two-ranked leaves and perfect flowers. 

 Perianth six-parted. Stamens 3, inserted on the perianth. Ovary infer- 

 ior, 3-celled, with many ovules. 



Style branches broad and petal-like. 1. /ps. 

 Style branches slender. 



Flowers 1^-'^' broad. 2. Gemmingia. 



Flowers less than 9^^ broad. 3. Sisyrinchium. 



1. IRIS L. Blue Flag. 

 Perennials with creeping rootstocks and showy flowers. Perianth seg- 

 ments clawed, the three outer spreading, the inner erect. Styles petaloid, 

 over-arching, bearing the stigmas under their 2-lobed apex. Capsule 3- 

 6-angled. 



Flowers on tall stems. 1. I. versicolor. 



Flowers hidden among the leaves. 2. I. foliosa. 



1. I. versicolor L. 2°-3° high : leaves somewhat glaucous : flowers 

 24^-3^ long, violet-blue, variegated with green, yellow or white : capsule 

 3-sided. — In swampy ground. Common from Adams to Lake City. 

 May-June. 



2. I. foliosa Mackenzie & Bush., n. sp. Stems flexuous : leaves often 

 2° long, not glaucous : flowers on pedicels 10^^-14^^ long : perianth seg- 

 ments bluish, 2Y long, spreading, not crested : capsule strongly 6-angled. 

 — Meadows and borders of low woods. Lake City, Adams, Glendale, 

 Little Blue Tank and Greenwood. Locally abundant. June. 



2. GEMMINGIA Fabr. 

 A tall perennial with 7m-like leaves and flowers in terminal panicles. 

 Perianth divisions distinct nearly to summit of ovary. Stamens mona- 

 delphous at base, inserted at base of perianth segments. Anthers oblong. 

 Capsule pear-shaped, the valves finally breaking and exposing the black 

 fleshy seeds. 



