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PHARMA COGNOSY. 
ored, the latter diverging at an angle of about 60°, 
curving upward and uniting near the margin ; under 
surface light green, slightly pubescent on the veins, 
glandular-pubescent ; petiole 4 to 10 mm. long, slightly 
pubescent. Inflorescence in axillary whorls or in in- 
terrupted spikes; peduncle wanting or about 3 mm. 
long, pedicel about 1 mm. long; calyx tubular, equally 
five-toothed, about 2 mm. long, purplish, glandular- 
punctate; corolla tubular, nearly regular, four-cleft, 
about 3 mm. long, purplish ; stamens four, erect, distant. 
Nutlets ellipsoidal, about 0 - 5 mm. in diameter, blackish 
brown. Odor aromatic. Taste aromatic, followed by 
a cooling sensation. 
Constituents. — Volatile oil, containing about 50 per 
cent, of menthol, about 1 per cent. ; resin and tannin. 
Allied Plants. — A number of other species of 
Mentha contain principles similar to those of M. pipe- 
rita ; of these may be mentioned M. arvensis var. pipe- 
rascens, yielding the Japanese peppermint and M. Cana- 
densis var. glabrata, yielding the Chinese peppermint, 
the oils from these plants being rich in menthol. 
MENTHA VIR1DIS (Spearmint). 
The leaves and flowering tops of Mentha spicata (Syn. 
Mentha viridis) (Fam. Labiatse), a perennial herb indige- 
nous to Europe and cultivated and naturalized in 
various parts of North America. It should be collected 
in the same manner as peppermint. 
Description. — Closely resembling peppermint (see 
Mentha Piperita), but the stems are usually more pur- 
ple, the leaves usually sessile, inflorescence either in 
slender interrupted cylindrical spikes or crowded 
lanceolate spikes, and the taste is not followed by a 
cooling sensation. 
Constituents. — Volatile oil about 0'5 per cent., con- 
