526 LABIATAE 
5. ORIGANUM, L. 
Herbs, sometimes shrubby plants, with opposite, nearly or quite entire 
leaves and with pink or purple flowers in dense spreading terminal clus- 
ters. Calyx bell-shaped, hairy in the throat, 5-toothed, 13-nerved; co- 
rolla 2-lipped, the upper lip erect, notched at apex, lower of 3 lobes. 
Stamens 4, the upper 2 extending above the upper lip, the shorter pair 
exserted from the corolla tube. 
O. vulgare, L. (Fig. 8, pl. 131.) Wirp MarvsoraM. Erect, hairy, 
the flower clusters spreading into broad nearly umbel-like groups. Leaves 
round egg-shaped. Roadsides. June-Oct. 
6. PYCNANTHEMUM, Michx. (Koellia, Moench) 
Upright herbs, with the odor of mint, with short spreading branches; 
leaves among the flower clusters often whitened; flowers small, white or 
dotted with purple. Calyx ovate or tubular, about 13-nerved, the 5 teeth 
being equal or the 3 upper teeth being more or less united, not hairy 
at the throat; corolla 2-lipped, the upper lip plane or notched at apex, 
the lower 3-cleft. Stamens 4, nearly equal, the lower pair somewhat the 
longer, the two sacs of the anther parallel. Ovary deeply 4-parted, the 
nutlets smooth or rough. 
Leaves linear or narrow lance-shaped. 
Plant not hairy or with few hairs. 
Calyx teeth bristle-tipped, nie 1/3 as long as the corolla tube 
P. flexuosum 
Calyx. teeth ‘triangular, t as long as tube oi' corolla : "Pp. virginianum 
Plant decidedly hairy. 
Calyx teeth bristle-tipped. 
Not) hairy, between teeth 2. = <9. = % P. verticillatum 
ong? hairs between teeth 5 2) 2 2 6 Pap! clinopodioides 
Leaves not linear or narrow lance-shaped. 
Calyx teeth bristle-tipped. 
Leaves with a minute hoary down, flowers in a dense head P. aristatum 
Leaves whitish downy above, with white wool beneath . P. incanum 
Galyx teeth’ “not bristle-tipped' "2 2 ss os « « PO muncum 
1. P. flexuosum, (Walt.) B. S. P. (Fig. r pl. 132.) Narrow- 
LEAVED MountTAIN Mint. (P. linifoliwm, Pursh.) Stem erect, stiff, slen- 
der, smooth, 14 to 24 ft. high. Leaves linear, tapering at both ends, 1 to 
3 ft. high. Leaves lance-shaped, rounded at base, tapering at apex. Calyx 
teeth triangular, hairy. Flowers in dense heads in spreading terminal 
clusters. Fields and thickets, Maine, southward and westward. July- 
Sept. 
2. P. virginianum, (L.) D. and J. (Fig. 1, pl. 132.) Viratnra Moun- 
TAIN Mint. (P. lanceolatum, Pursh.) Stem erect, stiff, not hairy, 1 to 
2 in. long. Flowers in compact terminal heads in spreading clusters. 
Calyx tubular, the 5 teeth equal, triangular, but each tipped with a short 
bristle point. Fields and thickets, Mass., and southward. July-Sept. 
3. P. verticillatum, (Michx.) Pers. (Fig. 8, pl. 132.) Torry’s 
Mountain Mint. (P. Torryi, Benth.) Slightly downy, stem 1 to 23 ft. 
high, erect, stiff, slender. Leaves lance-shaped, tapering at each end, 
without dentations at margins. Calyx teeth white-downy with bristle- 
shaped tips. Corolla downy, the tube somewhat exceeding the calyx. 
Dry hills, Vermont, southward and westward, July-Sept. 
