410 FLORA OF TEXAS. 



herhs ; ivUorls (in our species) approximate, forming a dense 

 or interrupted terminal spike. 



M. VIRIDIS, L. Stem and leaves smooth ; leaves ovate- 

 lanceolate, unequally serrate, nearly sessile ; brads leafy, and 

 like the calyx, smooth or hairy; spike cylindrical, inter- 

 rupted below; calyx-iQQth. linear-subulate. (M. tenuis, 

 Michx.) Damp soils. Stem l°-2° high.', jloioers pale blue. 



M. ROTUNDiFOLiA, L. Soft-hairy ; stem erect; leaves 

 roundish, rugose, crenate, sessile, hoary beneath; spikes 

 oblong, interrupted ; tracts lanceolate ; fruiting calyx 

 roundish ; the teeth short and acute. Stem l°-2° high ; 

 corolla white. 



LYCOPUS, L. 



Calyx bell-shaped, equally 4-5-toothed, naked at the 

 throat ; corolla bell-shaped, exserted, equally 4-cleft ; fertile 

 stamens 2, exserted, the upper pair sterile, included or 

 wanting; anther-cells parallel; style 2-cleft at the apex; 

 nutlets 3-angled, truncate at the apex, narrowed at the 

 base. — Marsh or aquatic herhs^ with long runners at the 

 base; leaves mostly toothed or pinnatifid; whorls dense, 

 axillary ; floivers small, sessile. 



L. ViRGiNicus, L. Ste7n smoothish ; leaves ovate-lan- 

 ceolate, toothed-serrate, acute or acuminate at each end, 

 roughened above ; calyx-teeth 4, ovate, obtuse; corolla small, 

 exserted; sterile stamens minute. Ponds and ditches. 

 September. Stem l°-2° high; leaves l'-2' long; Jloiuers 

 white. 



PYCNANTHEMUM, Michx. Horse-mint. 



Calyx tubular, 13-nerved, naked in the throat, equally 

 5-toothed, or slightly 2-lipped; corolla 2-lipped, the upper 

 lip notched or entire, the lower 3-cleft ; stamens 4, nearly 

 equal, straight, spreading, commonly exserted ; anther-cells 

 parallel ; style 2-cleft at the apex ; mitlets smooth.^Peren- 



