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AMERICAN MEDICTXAl. LEAVES AND HERBS. 



PEXXYROYAL. 



Iledcnma pulegioides (L.) Pers. 



T'harmacopoeial name. — Heck'oma. 



Other common names. — American pennyroyal, mock pennyroyal, squaw mint, tick- 

 weed, stinking balm, mos- 

 quito plant. 



Habitat and range. — Pen- 

 nyroyal is found in dry soil 

 from Nova Scotia and 

 Quebec to Dakota and 

 southward. 



Description. — This very 

 strongly aromatic annual 

 of the mint family (Men- 

 ihacese) is of rather insig- 

 nificant appearance, being 

 a low-growing plant, about 

 6 inches to a foot or so in 

 height, with a slender, 

 erect, much-branched and 

 somewhat hairy stem. 



•The opposite leaves are 

 small, scarcely exceeding 

 three-fourths of an inch in 

 length and becoming 

 smaller toward the top of 

 the plant. They are borne 

 on short stems and are ob- 

 long ovate in shape, thin, 

 blunt at the apex, nar- 

 rowed at the base, and with 

 margins sparingly toothed. 

 The branchlets are four an- 

 gled and somewhat hairy, 

 and the loose flower clus- 

 W' / ters, appearing from July to 



J-' 1 September in the axils of 



the leaves, consist of a few 



pale-bluish flowers with 2- 



uppcr tine enlirc or slightly notched or two lubed, while the 



I'Ki. Is.— Tennyroyal (Iltdeoma pukgiuidm), leaves and llower.s. 



lipped cijroUa, the ere<l 



lower spreading lip is three cleft. (I''ig. 18.) 



Collection, prices, and uses. — The leaves and flowering t()j)s are otticial in the United 

 States Pharmacopoeia, as is also the oil of pennyroyal distilled from them. They 

 should be collected while in flower. The price paid to collectors ranges from about 

 1^ to 21 cents a pound. 



Pennyroyal has a strong mintlike odor and pungent taste and is used as an aromatic 

 stimulant , carniinati\e, and emmenagogue. The odor is very repulsive to insects, and 

 pennyroyal is therefore much used for keeping away mosquitoes and other trouble- 

 some in.sects. 

 i'19 



