CISTACEAE 213 



10. Hjrpericum mutilum L. Dwarf St. John's-wort. (Man. p. 

 628; I. F. /. 24^8.) In low grounds, N, S. to Man., Fla., Kans., and 

 Tex. — Pennsylvania : Monroe ; Northampton ; Bucks ; Montgom- 

 ery ; Philadelphia ; Delaware ; Chester ; Lancaster ; Dauphin ; 

 Franklin ; Huntingdon ; Erie ; Allegheny. 



11. Hypericum gymnanthum Engelm. Clasping-lEaved St. 

 John's-wort. (Man. p. 628; I. F./. ^^59.) In low ground.", N. J. and 

 Del. to Minn., La. and Tex. — Pennsylvania: Bucks, Bristol; Dela- 

 ware, Tinicuni. 



12. Hypericum majus (A. Gray) Britton. Larger Canadian St. 

 John's-wort. (Man. p. 628; I. F. f. 2460.) In moist soil, Me. to 

 Mich., N. J., and Neb. — Pennsylvania : EriE, Presque Isle. 



13. Hypericvun Cauadense L. Canadian St. John's-wort. (Man. 

 p. 628; I. F. f. 2461.) In wet, sandy soil, Newf. to Man., Ga., Ky. and 

 Wis. — Pennsylvania : Monroe ; Northampton ; Bucks ; Delaware, 

 Tinicum ; Chester ; Lancaster ; York ; Schuylkill ; Huntingdon ; 

 Erie, Presque Isle ; Fayette. 



3. SAROTHRA L. 

 1. Sarothra gentianoides L. Orange-GRass. Pine-weed. (INIau. 

 p. 628 ; I. F./. 246J.) In sandy soil, Me. to Fla., Ont., Minn., Mo. and 

 Tex. — Pennsylvania : Monroe ; Northampton ; Delaware ; Ches- 

 ter ; Lancaster; York; Schuylkill; Bedford; Huntingdon; 

 Allegheny. 



4. TRIADENUM Raf. 



Leaf-blades sessile and partly clasping : flower-clusters peduncled. 



I. T. Ftrginicuin. 

 Leaf-blades petioled : flower-clusters sessile or nearly so. 2. T. peiiolatum. 



1. Triadenum Virginicum (L.) Raf. Marsh St. John's-wort. 

 (Man. p. 629 ; I. F. /. 2464.) In swamps, Lab. to Fla., Man., Neb. and 

 La. — PeJinsylvattia : Monroe ; Northampton ; Bucks ; Montgomery ; 

 Delaware ; Chester ; L.'Vncaster ; York ; Schuylkill ; Luzerne ; 

 Franklin ; Clarion ; Crawford ; Allegheny. 



2. Triadenum petiolatum (Walt.) Britton. Larger Marsh St. 

 John's-wort. (Man. p. 629; I. F. /. 246^.) In swamps, N. J. and Md. 

 to Fla., Ark. and La. — Pennsylvania: Philadelphia (Bartram's Gar- 

 den); Crawford; Erie. 



Family 2. ELATINACEAE Lindl. Water-wort Family. 

 1. ELATINE L. 

 1. Elatine Americeina (Pursh) Arn. Water -wort. Mud-purslane. 

 (Man. p. 629 ; I. F. /. 2466.) Margins of ponds and slow streams, Me. 

 and Ont. to Va., Mo. and Tex. — Pennsylvania : Philadelphia ; Dela- 

 ware, Tinicum. 



Family 3. CISTACEAE Lindl. Rock-rose Family. 

 Corolla yellow : petals 5, fugacious or wanting. i. Helianthemxjm. 



Corolla not yellow : petals 3, persistent. '2. Lechea. 



