FLOKA OF THE DISTKICT OF COLUMBIA. 217 



Branches of the umbel glabrous; fruit not winged. 

 Leaflets deeply lobed; bracts present at the base of the umbel; 

 calyx teeth none; ribs of the fruit slender, not corky. 



17. CONITJM. 



Leaflets evenly toothed; bracts none or soon deciduous; calyx 



teeth present; ribs 'of the fruit thick, corky 20. CICTJTA, 



1. EBYNGIUM L. 



Leaves net-veined; bracts at the base of the head toothed 1. E. virginianum. 



Leaves parallel- veined; bracts entire 2. E. aquaticum. 



1. Eryngium virginianum Lam. 



Marshes along the lower Potomac and its tributaries; frequent. July-Oct. N. J. 

 i;o Tex. 



2. Eryngium acmatioum L. Button snakeroot. 

 Dry sandy bank, Cabin John, Aug., 1904 (/. H. Painter). Eastern and central 



U. S. (E. yuccaefoiium Michx.) 



Eryngium planum L., a European species with broad cordate leaves, was collected 

 along Massachusetts Avenue in 1899 (Steele), 



2. SANICULA L. Bur snakeroot. 



Styles shorter than the bristles of the fruit; staminate flowers not in separate heads; 



flowers white * 1.8. canadensis. 



Styles longer than the bristles; staminate flowers partly in separate heads; flowers 

 greenish yellow or greenish white. 

 Calyx teeth lanceolate; fruit about 6 mm. long; flowers greenish white. 



2. S. marylandica. 

 Calyx teeth ovate; fruit about 3 mm. long; flowers greenish yellow.. 3. S. gregaria. 



1. Sanicula canadensis L. 



Damp woods; common. May-June. Widely distributed in N. Amer. 



2. Sanicula marylandica L. 



Damp woods, chiefly along Rock Creek and the upper Potomac; frequent. May- 

 June. Widely distributed in N. Amer. 



3. Sanicula gregaria Bicknell. 



Moist woods, chiefly westward. May. Eastern N. Amer. 



3. DAUCUS L. 

 1. Daucus carota L. Carrot. 



Dry fields and waste ground; abundant. May-Aug. Native of Eur. and Asia; 

 widely naturalized in N. Amer. 



The flowers are white, but the central one of the umbel is usually dark purple; 

 sometimes all the flowers are pinkish. 



4. TOBILIS Adans. 



1. Torilis anthriscus (L.) Gmel. Hedge parsley. 



Waste ground about Washington; probably not established. June-July. Native 

 of Eur.; adventive in the eastern U. S. (Caucalis anthriscus Huds.) 



5. OSMOBRHIZA Raf. 



Style and its base together 1 mm. long or shorter; plants very hairy. ..1. O. claytonl. 



Style and base together 2-4 mm. long; plants nearly glabrous 2. O. longistylis. 



1. Osmorrhlza claytoni (Michx.) Clarke. 



Moist woods; common. May. Eastern N. Amer. (0. brevisty lis DC; Washing tonia 

 claytoni Britton.) 



The roots of this and the following species are edible; the flavor resembles that of 

 anise. 



