208 



LABIATE. 



Perennial herbs with flowers in dense whorls, arranged in terminal or 

 axillary heads or spikes. Corolla pale purple or whitish. 



Mentha piperita Linne. — Peppermint. 



Description. — Smooth. Stem erect, 1 to 2 feet high. Leaves ovate-ob- 

 long, and lanceolate, serrate, petiolate. Inflorescence mostly terminal, in 

 interrupted heads or spikes. 



Fig. 143. — Mentha'piperita. 



Fig. 144. — Mentha viridis. 



Habitats — Naturalized from Europe ; growing in low grounds and wet 

 places. It is extensively cultivated in some sections of the country, nota- 

 bly in Wayne County, New York, for the sake of its volatile oil. It multi- 

 plies rapidly by means of underground shoots. 



Mentha viridis Linne. — Spearmint. 



Description. — Nearly smooth. Stem erect, 1 to 2 feet high. Leaves 

 oblong-lanceolate, acute, unequally serrate, nearly sessile. Inflorescence 

 terminal, in narrow, interrupted spikes. 



Habitat. — Naturalized from Europe ; growing in damp soil along road- 

 sides and in waste places. 



Parts Used. — The leaves and tops of both species — United States 

 Pharmacopoeia. 



Constituents.— -The only important constituent of mint is its volatile 

 oil. 



