318 ENDOGENOUS PLANTS 



2 I. Virginica, L. Stem slender, terete; leaves narrowly 

 lance-linear; ovary with the sides 2-grooved; capsule acute at 

 both ends. 

 VIRGINIAN IRIS. Slender blue Flag. 



Stem 1 to 2 feet high, marked with a prominent line on opposite sides, but not 

 ancipital. Leaves usually overtopping the stem. Flowers 3 to 6 or 8 in a ter- 

 minal raceme, smaller and more yellow than the preceding. 

 Hob. Wet meadows; along Brandy wine : rare. Fl. June. Fr. 



Obs. Collected in 1838, by Mr. ALBERT TOWNSEND. 

 432. SISYRUV'CHIUM, L. 



[Or. Sys, a hog, and Rhynchos, a snout; hogs being supposed fond of rooting it up.] 

 Perianth with the 6 deeply-parted lobes alike, and spreading. 

 Stamens monadelphous. Stigmas involute-filiform, acute, alternat- 

 ing with the stamens. Capsule membranaceous, roundish-obovoid, 

 slightly trigonous ; seeds sub-globose. Grass-like perennials: roots 

 fibrous; stems slender, cespitose, winged or ancipital; leaves chiefly 

 radical ; flowers blue, small, in umbellate clusters of 3 to 6, from 2 

 spathe-like bracts. 



1. S. Ilcrimidiana, L. Stem winged, nearly leafless, often 

 branched above ; bracts shorter than the peduncles. 

 S. anceps. Cavan. $ FL Cestr. ed. 2. p. 13. 

 BERMUDIAN SISYRINCHIUM. Blue-eyed Grass. 



Stem 9 to 18 inches high, compressed, with a broad margin on each side, and a 

 sheathing leaf at the base of the branches. Leaves 3 to 12 inches long, linear, 

 ensifbrm, acute. Bracts nearly equal, lanceolate, 2- to 5-flowered. 



Var. mucronatum, A. Gray. Stem ancipital, simple, leafless; bracts unequal, 

 colored, the outer one cuspidate, longer than the peduncles. 

 S. mucronatum. MX. and Fl. Cestr. ed. 2. p. 12. 

 Hob. Low grounds ; meadows, and thickets : frequent. Fl. May, June. Fr. July . 



Obs. The S. mucronatum of MX. which is every way more slender 

 and delicate than the other, is reduced to a var. by Prof. A. GRAY. 



ORDER CIX. DIOSCOREA'CEAE. 



Mostly Jierbs; rhizomas tuberous, or nodose; stems slender and twining; leaves 

 chiefly alternate, ribbed, netted-veined, petiolate, without stipules ; flowers dioi- 

 cous, regular; perianth 6-cleft: STAM. FL. with 6 stamens, inserted on the base of 

 the perianth-lobes ; anthers introrse : PISTILL. FL". with the perianth-tube adherent 

 to the 3-celled ovary; styles 3, distinct ; fruit a membranaceous 3-winged few-seeded 

 capsule or sometimes baccate; seeds compressed and margined, or subglobose ; 

 embryo in cartilaginous albumen. 



433. DIOSCORITA, L. 



[Dedicated to the ancient Greek Naturalist, Dioscorides.] 

 Generic character nearly that of the Order: Capsule 3-celled, loculi- 

 cidally 3-valved by splitting through the prominently winged angles. 

 Seeds 1 or 2 in each cell, flat and margined. Perennials: stem 

 volubile ; flowers pale green, in axillary panicles and racemes. 



1. D. villdsa, L. Herbaceous; leaves cordate, acuminate, pubes- 



