CISTACE^. (nOCK-KOSE FAMILY.) 35 



base. Style hooked at the summit. — An upriL;ht simple hairy perennial herb, 

 with numerous ovate-laneeolate, acuminate and entire leaves, and 1-3 short- 

 stalked greenish nodding flowers in each axil. 



1. S. COncolor, Ging. — Mountains of Carolina and northward, in deep 

 shades. June and July. (Viola eoneolor, Pursh.) — Stem 1° - 2° liigh. Leaves 

 short-petioled. 



Ordku 15. CISTACEiE. (Rock-kose Family.) 



Herbs or low shrubs, with entire leaves, and regular mostly polyandrouK 

 flowers. — Sepals 5, persistent, the two outer ones smiiUer, the three inner 

 twisted in the bud. Petals mostly 5, twisted contrary to the sepals in the 

 bud, rarely wanting. Stamens few or numerous, distinct, hypogynous. 

 Anthers innate. Ovary 1-celled. Style single. Capsules 3-5-valved. 

 bearing as many parietal placentae each in the middle of the valve, few oi 

 many-seeded. Seeds orthotropous. Embryo curved, in mealy albumen- 

 Synopsis. 



1. nELIANTUEMUM. Style none. Stigma capitate. Embryo nearly annular. 



2. LECIIKA. Styie none. Stigmas plumose. Embryo nearly straight. 



3. HUDsONIA- Style filiform Stigma minute. Embryo coiled. 



1. HELIANTHEMUM, Tourn. Kock-rose. 



Petals 5, corrugated in the bud, sometimes wanting. Stigma sessile or nearly 

 so, capitate, 3-lobed. Capsule 3-valved. Embryo cui'ved nearly into a ring. — 

 Low herbs or partly shrubby plants, with fugacious yellow flowers. 



* Flotoers perfect : petals conspicuous : stameits indefinite : capsule many-spcded. 



1. H. Carolinianum, Michx. Hirsute; leaves lanceolate, denticulate, 

 acute, siiort-petiolcd, the lowest obovatc, crowded ; flowers large, solitary, borne 

 above the axils. — Dry sandy soil, Florida to North Carolina and westward. 

 March and Apfil. — Stems 6' -12' high, ascending from a shrubby base. 

 Flowers 1' wide. 



2. H. arenicola, sp. n. Hoary ; leaves small, lanceolate, obtuse, entire, 

 with the sides revolute; flowers solitary, or 2-4 in terminal umbellate clusters, 

 on slender pedicels. — Drifting sands near the coast. West Florida. March and 

 April. — Stems shnibby and branched at the base, all but the short (2'- 6') 

 flowering stems buried in the sand. Flowers ^' wide. 



* * Flowers of two kinds : the earliest as in the last section, the later ones smaller, 

 clustered, with small petals, or none, fewer stamens, and few-seeded capsules. 



3. A. COrymbosum, Michx. Tomentose, stems erect, shrubby at the 

 base ; leaves lanceolate, obtuse, entire, hoary beneath, with the sides revolute ; 

 flowers nearly sessile in a cymose cluster at the summit of the stem, the perfect 

 ones long-ped uncled ; sepals woolly. — Dry sands near the coast, Florida to 

 North Carolina. April. — Stems 1° high. Capsule smooth. 



