766 MISC. PUBLICATION 42 3, U. S. DEPT. OF AGRICULTURE 



2. Leaf blades entire or sparsely and irregularly denticulate, lance-oblong, dull 

 green and scarcely rugose above; young stems canescent-puberulent; 

 corolla pale blue 1. L. ligttstrina. 



2. Leaf blades regularly crenate with numerous teeth, ovate or suborbicular, 



bright green and rugose above, whitish beneath; young stems finely 



whitish tomentose; corolla whitish 2. L. wrightii. 



1. Plants herbaceous, not aromatic; leaf blades cuneate, serrate, strigose but 

 scarcely scabrous; inflorescences few, dense, short-spicate or subcapitate, 

 not more than 4 times as long as wide; bracts broad, imbricate, closely 

 subtending the flowers; calyx strigose; stems procumbent, rooting at the 

 nodes: Subgenus Phyla (3). 



3. Leaf blades rigid, thick, oblanceolate-cuneate, with 1 to 4 pairs of teeth 



near the apex; herbage strigillose-canescent 3. L. cuneifolia. 



3. Leaf blades not rigid, thin, lanceolate to rhombic-ovate, with more than 

 4 pairs of teeth, these extending well below the apex; herbage green. 



4. L. LANCEOLATA. 



1. Lippia ligustrina (Lag.) Britton, N. Y. Acad. Sci. Trans. 9: 181. 



1891. 



Verbena ligustrina Lag., Gen. et Sp. PL 18. 1816. 



Near Ruby, Santa Cruz County, about 4,000 feet (Harrison and 

 King 6964). Western Texas, southern Arizona, and Mexico. 



2. Lippia wrightii A. Gray, Amer. Jour. Sci. ser. 2, 16: 98. 1853. 

 Grand Canyon (Coconino County) and northern Mohave County 



to Greenlee, Cochise, Pima, and Yuma Counties, 2,000 to 6,000 feet, 

 common on dry rocky slopes, August to October. Western Texas to 

 southeastern California and northern Mexico. 



Reported as growing only on northern slopes at low altitudes and 

 only on southern exposures at its higher altitudinal limit. 



3. Lippia cuneifolia (Torr.) Steud. in Marcy, Expl. Red River 293. 



1854. 



Zapania cuneifolia Torr., Ann. Lye. N. Y. 2: 234. 1828. 

 Phyla cuneifolia Greene, Pittonia 4: 47. 1899. 



Apache County to eastern Coconino County and along the Colorado 

 River at Fort Mohave and near Yuma, stream beds and "playas," 

 usually in heavy soil, June to August. Nebraska and Wyoming to 

 Texas and Arizona. 



A form collected in the White Mountains (Ellis 4) approaches Phyla 

 incisa Small in its elongate peduncles. 



4. Lippia lanceolata Michx., Fl. Bor. Amer. 2: 15. 1803. 



Phyla lanceolata Greene, Pittonia 4:47. 1899. 



Tucson, Pima County (Tourney in 1892), also at St. Thomas, 

 Nevada, very near the northwestern border of Arizona (Purpus 6180). 

 New Jersey to Minnesota, Florida, Texas, Arizona, and southern 

 California. 



4. BOUCHEA 



Plant annual; stem erect, leafy, sparingly branched; leaves long- 

 petioled, the blades oval or ovate, crenate or serrate; flowers in slender 

 elongate spikes; corolla deep violet. 



