CI ST ACE AE. 225 



Burlington— Mediord (Br.)- Gloucester^ Near Mickleton, Dr. J. B. 

 Brinton (He.). 



New Castle— Townsend, Canby and Tatnall. 

 11. Hypericum Canadense L. M. p. 628. Wet, sandy soil. Summer. 



3. SAKOTHRA L. 

 1. Sarothra gentianoides L. Orange-grass, Pine-weed. M. p. 628. Dry, 

 sandy soil. Summer. 



4. TRIADENUM Raf. Marsh St. John's-wort. 



Leaves sessile; flower-clusters peduncled. 1. T. Virginicum. 



Leaves short-petioled ; flower-clusters nearly sessile. 2. T. petiolatum. 



1. Triadenum Virginicum (L.) Raf. M. p. 629. Swamps. Summer. 



2. Triadenum petiolatum (Walt.) Britton. M. p. 629. Swamps. Sum- 



mer. 

 Philadelphia — Bartram's Garden (P.). 

 CawdcH — Camden (C). 

 New Castle — St. George 's, Canby. 



Family 3. ELATINACEAE Lindl. Water-wort Family. 

 1. ELATINE L. 

 1. Elatine Americana (Pursh.) Arn. Water-wort. M. p. 629. Margins 

 of ponds and streams. Summer. 

 Philadelphia — Philadelphia (Ca.). Bucks — Andalusia, shore of Dela- 

 ware, Mart. (B. C.). Delaware — Tinicum near Ice-house, A. R. Smith 

 (Fu.). 



Camden — Delaware River in tidal mud (C). Gloucester — Weuonah 

 (Gi.). Ocean— Terrago Pond (C). 

 Netv Castle — Muddy shores of Brandywine Creek. 



Family 4. CISTACEAE Lindl. Rock Rose Family. 



Petals 5, yellow, fugacious, or wanting. 



Leaves broad, lanceolate, or oblong. 1. Helianthemum. 



Leaves subulate or scale-like, imbricated ; style long. 2. Hudsonia. 

 Petals 3, not yellow, persistent ; flowers minute ; style none. 



3. Lechea. 



1. HELIANTHEMUM Pers. Frost-weed. 



Petaliferous flowers 5-12, in terminal clusters. 1. R. majus. 



Petaliferous flowers solitary or rarely 2. 2. R. Canadense. 



1. Helianthemum majus (L.) B. S. P. M. p. 630. Dry soil. Early 



summer. 

 Bucks — ( P. ) . M ontgom ery — ( P. ) . 



2. Helianthemum Canadense (L.) Michx. M. p. 631. Sandy or gravelly 



dry soil. Early summer. 



2. HUDSONIA L. 



Flowers slender-pedicelled ; leaves subulate. 1. R. ericoides. 



Flowers nearly sessile; leaves scale-like. 2. R. tomentosa. 



