103 



411. LAVANDULA VERA, continued. 



b. Essential oil. 



Note. Lavandnla vera may be distinguished from L. spica by having 

 rhomboidal bracts, those of L. spica being linear. For cultivation, see 

 P. J. [2], vol. i., p. 276; [8], vol. iii., p. 826. For results of distilla- 

 tion, P. J. [1], vol. viii., p. 276; [1], vol. x., p. 172. For adulteration, 

 see P. J. [1] , vol. xi., pt 82. Turpentine may be detected by its insolu- 

 bility in spirit ; alcohol may be removed, if present, by anhydrous chloride 

 of calcium or glycerin. Bentley and Trimen, Med. Plants, tab. 199. 



412. MENTHA PIPERITA, L. (Peppermint.) 



a. Herb. See Bentley and Trimen, Med. Plants, tab. 203. 



b. Essential oil. 



Note. Peppermint is known from spearmint by its purple tint, by the 

 leaves being stalked, and by the terminal spike-like inflorescence being 

 obtuse. For cultivation, see P. J. [1] , vol. x., p. 840. The oil has been 

 found adulterated with castor oil, spirit of wine, and turpentine. For 

 detection of these and other adulterations, see P. J. [1] , vol. ix., p. 580 ; 

 [3], vol. ii., p. 981; Cooley's Cyclopedia, p. 834. For fluorescence with 

 acids, P. J. [3], vol. i., p. 682; [3], vol. iv., p. 977. Hotchkiss' oil of 

 peppermint is known by giving an opalescent solution with rectified 

 spirit of wine, P. J. [3] , vol. ii. p. 338. The dried herb yields from 

 three to four times more volatile oil than in the green state. 



413. MENTHA VIRIDIS, L. (Spear-mint, Garden Mint.) 



a. Herb. See Bentley and Trimen, Med. Plants, tab. 202. 



b. Essential oil. 



Note. The oil of spearmint of commerce is chiefly derived from 

 Mentha aquatica, L., var. y crispa, Benth. See Pharmacographia, p. 432. 



414. MENTHA PDLEGIOM, L. (Pennyroyal, Organs.) 



a. Herb. See Bentley and Trimen, Med. Plants, tab. 201. 



b. Essential oil. 



Note. Pennyroyal is distinguished from the other official mints by the 

 small size of its leaves, and by the whorls of the flowers being distinct 

 and not arranged in a dense spikelike infloresence. See Hedeoma 

 pulegioides, and note under Origanum vulgare. 



415. MONARDA PDNCTATA, L. (American Horsemint.) 



a. Herb. 



b. Essential oil. 



Note. The leaves and tops are official in theU. S. Pharmacopoeia. The 

 plant possesses stimulant, anti-emetic, and emmenagogue properties. 

 See Amer. Dispens., p. 530. In this country Mentha sylvestris, L., is 

 known by the name of Horsemint. Bentley and Trimen, Med. Plants, 

 tab. 208. 



416. ORIGANUM VULOARB, L. (Wild Marjoram.) 



a. Essential oil. 



Note. The Marjoram of the kitchen gardens is 0. Majorana, L., and is 

 commonly known as " Sweet Marjoram." Pennyroyal is known in the 

 S. W. of England under the name of " Organs," a corruption of Ori- 



