FLORA OF THE DISTRICT OF COLUMBIA. 239 



8. LYCOPSIS L. 



1. Lycopsis arvensis L. Bugloss. 



Collected in several places within our area; probably not established. June- 

 July. Native of Eur. and Asia; occasionally adventive in eastern N. Amer. 



9. ECHKTM L. 

 1. Echium vulgare L. Viper's bugloss. 



Old fields; occasional. June-July. Native of Eur.; widely naturalized in N. 

 Amer. 



White-flowered plants are sometimes found. 



134. VERBENACEAE. Vervain Family. 



Plants erect; corolla 5-lobod; fruit composed of 4 nutlets; flowers in long spikes. 



1. VERBENA. 



Plants prostrate or ascending; corolla 4-lobed; fruit of 2 nutlets; flowers in short 



headlike spikes 2. LIPPIA. 



1. VERBENA L. 



Leaves deeply lobed; plants annual. Corolla white; fruit in interrupted spikes. 



1. V. officinalis. 

 Leaves merely toothed; plants perennial. 

 Leaves linear to oblanceolate, broadest above the middle. Corolla purple or blue; 



spikes dense, the fruits overlapping 2. V. angustifolia. 



Leaves ovate or lanceolate, broadest near the base. 



Spikes crowded, dense; corolla blue or pink .3. V. hastata. 



Spikes slender, interrupted, the flowers not overlapping; corolla white. 



4. V. urticifolia. 



1. Verbena officinalrs L. European vervain. 

 Waste ground about Georgetown and Alexandria. June-Aug. Native of Eur.; 



naturalized in many parts of the U. S. 



2. Verbena angustifolia Michx. Narrow-leaf vervain. 

 Open fields; common. July-Aug. Eastern IT. S. 



3. Verbena hastata L. Blue vervain. 

 Damp soil; frequent. July-Aug. Eastern N. Amer. 



4. Verbena urticifolia L. White vervain. 

 Open fields; frequent. July-Aug. Eastern N. Amer. 



2. LIPPIA L. 



1. Lippia lanceolata Michx. 



Wet flats along the Potomac. July-Aug. Eastern N. Amer. (Phyla lanceolata 

 Greene.) 



135. MENTHACEAE. Mint Family. 



Inflorescence composed of denBe axillary whorls, compact heads, or close Bpikes. 

 Flowers axillary, without conspicuous colored bracts, sessile. 



Plants densely white-woolly 6. M ARRTTBITTM . 



Plants glabrous or hairy, not densely woolly. 

 Corolla strongly 2-lipped; leaves rounded or cut-lobed. 

 Upper leaves wedge-shaped at the base, sharply lobed; plants tall, erect. 



13. LEONURTJS. 

 Upper leaves heart-shaped or clasping; plants low, often trailing. 



12. LAMITJM. 



