SPECIES AND VARIETIES. 383 



obtuse, slightly crenate, all similar ; flowers in distant, globose, 

 many -flowered semi-whorls, small, lilac. A small, creeping, 

 powerfully-scented medicinal herb. Penny-royal. Wet 

 places. Fl. August, September. 



(43) Lamium. 



L. amplexicaule : annual ; stem dwarf, decumbent ; leaves 

 roundish-cordate, obtuse, inciso-crenate, the lower ones stalked, 

 the upper sessile, clasping; flowers in 1-3 compact semi- whorls, 

 the corolla purple, its tube slender, much longer than the 

 softly hairy calyx ; lateral lobes of the lower lip of the corolla 

 toothless. Henbit Nettle. Waste and cultivated ground. 

 Fl. May to September. 



L. purpureum : annual, with low spreading stems ; leaves 

 cordate-obtuse, crenate-serrate, stalked, the upper ones 

 crowded, shortly-stalked, ovate; flowers pale purple, the lip 

 spotted with red, the lateral lobes of the lower lip of the 

 corolla with two teeth. Red Dead-nettle. Waste and culti- 

 vated ground. Fl. May to September. 



(44) Chenopodium. GOOSE FOOT. 



C. polyspermum : annual; stem erect or procumbent; 

 leaves ovate-elliptical, sessile, acute or obtuse; flowers in 

 axillary leafless cymose or spicate racemes, small, incon- 

 spicuous. Damp waste places. Fl. August, September. 



(45) Spiranthes. LADY'S TRESSES. 



S. autumnalis: tuberous; stem 4-6 inches high; radical 

 leaves ovate-oblong, those of the stem bract-like ; spike spiral, 

 dense; flowers greenish-white, the column and its lid acute 

 with an obtuse-ovate membranous process between them 011 



