70 KEY TO THE SPECIES 



1. MONARDA (Horse Mint) 



Odorous erect herbs with entire or toothed petioled leaves, rather large flowers" 

 in whorled heads closely surrounded by bracts, elongated tubular 5-toothed calyx, 

 strongly 2-lipped elongated corolla, upper lip erect and entire or notched, lower 

 lip 3-lobed at apex, and 2 elongated ascending stamens. 



1. Monarda menthtefolia Graham (.Rocky Mountain Horse Mint). Mi- 

 nutely appressed-pubescent, with a slightly glaucous hue ; 3-7 dm. high, simple 

 or somewhat branched above ; leaves ovate-lanceolate, serrate ; heads solitary, 

 terminating the stem and branches (if any) ; calyx slightly hairy in the throat ; 

 corolla lilac, somewhat purplish- dotted ; stamens protruded beyond the upper lip. 

 Frequent in the valleys of the foothills. 



2. Monarda NuttalUi Aven Nelson (Nuttall's Monarda). Puberulent up- 

 wardly, somewhat whitened and the foliar bracts tinged with purple, 2-4 dm. 

 high ; leaves lanceolate or narrower ; the bracts oblong, the mid-nerve prolonged 

 into an aristate tip ; heads in the axils of the uppermost pairs of leaves ; calyx- 

 teeth aristate and soon spreading, ciliate-bearded ; corolla white or pinkish, not 

 spotted but more or less punctate. Dry plains. 



2. HEDEOMA (Pennyroyal) 



Cinerous-puberulent perennials, aromatic, flowers in small axillary cymes, 

 whitish or purplish corolla, perfect stamens only two, sterile ones (staminodia) 

 minute, and nutlets smooth and ovoid. 



I. Hedeoma Drummondii Benth. (Drummond's Pennyroyal). Freely 

 branched from a somewhat woody base, from 5-15 cm. high ; leaves oblong to 

 linear, obtuse ; calyx hirsute, with subulate teeth, becoming closed in fruit ; co- 

 rolla purple. Dry caiions and slopes. 



3. MENTHA (Mint) 



Fragrant herbs with small purple or whitish flowers in close axillary clusters 

 or spicate, bell-shaped or tubular 5-toothed calyx, corolla with short tube and a 

 bell-shaped 4-cleft border (upper lobe largest, entire or 2-cleft), and 4 equal and 

 distant stamens. (See Plant Structures, p. 289, Fig. 213.) 



3. Mentha Canadensis L. (American Wild Mint). Perennial by rhizomes, 

 from nearly glabrous to distinctly hairy, 1-3 dm. high ; stems simple or branched ; 

 leaves mostly ovate-lanceolate, serrate, petioled, the uppermost axils fiowerless ; 

 calyx hairy, its teeth one fourth as long as the campanulate tube. General ; wet 

 banks, both plains and mountains. 



4. DRACOCEPHALUM 



Mostly coarse herbs, with large, leafy bracted, terminal clusters of flowers, 

 with 2-lipped calyx, 2-lipped corolla, anther cells (sacs) divaricate and nutlets 

 smooth. 



1. Dracoceplialuni parviflorum Nutt. (American Dragon-head). Slightly 

 pubescent, 3-6 dm. high, usually several or many stemmed from the base ; leaves 

 from ovate to lanceolate, serrate or incised ; flowers in thick heads or spikes, 

 mostly terminal ; corolla light-blue, nearly included ; its upper lip emarginate. the 

 lower 3-lobed. Dry gravelly soil. 



