300 LABIATJE. (MINT FAMILY.) 



1. P. Leptostachya, L. Rich copses, common July. Plant 2 

 3 high : leaves 3' -5' long, thin. (Also in the Himalaya Mountains !) 



ORDER 77. LABIAT^R. (MINT FAMILY.) 



Chiefly herbs, with square stems, opposite aromatic leaves, more or less 2- 

 lipped corolla, didynamous or diandrous stamens, and a deeply 4-lobed ovary, 

 which forms in fruit 4 little seed-like nutlets, or achenia, surrounding the base 

 of tlie single style in the bottom of the persistent calyx, each filed with a sin- 

 gle erect seed. Albumen mostly none. Embryo straight (except in Scu- 

 tellaria) : radicle at the base of the fruit. Upper lip of the corolla 2- 

 lobed or sometimes entire ; the lower 3-lobed. Stamens, as in all the al- 

 lied families, inserted on the tube of the corolla. Style 2-lobed at the 

 apex. Flowers axillary, chiefly in cymose clusters, which are often aggre- 

 gated in terminal spikes or racemes. Foliage mostly dotted with small 

 glands containing a volatile oil, upon which depends the warmth and aro- 

 ma of most of the plants of this large and well-known family. (More abun- 

 dant in the Old World than the New. One third of our genera and many 

 of the species are merely introduced plants.) 



Synopsis. 



TRIBK I. A JUGOIDE^. Stamens 4, ascending (curved upwards) and parallel, usually 

 projecting from the notch of the upper side of the (not evidently 2-lipped) 5-lobed enroll i. 

 Nutlets reticulated and pitted, obliquely attached by the inside near the base. 

 * Lobes of the corolla all declined (turned forwards) : stamens exserted. 



1. TEUCRIUM. Lower lobe of the corolla much larger than the others. Calyx 5-toothed. 



2. TRICHOSTEMA. Lobes of the corolla scarcely unequal. Calyx 5-cleft, oblique. 



* * Lobes of the corolla almost equally spreading : stamens nearly included. 



3. ISANTHUS. Calyx bell-shaped, 5-cleft, almost equalling the small corolla. 



TRIBE II. SATUREIE^i. Stamens 4, the inferior pair longer, or only 2, distant, 

 straight, diverging, or converging under the upper lip : anthers 2-celled. Lobes of the 

 corolla flat and spreading Nutlets smooth or minutely roughened, fixed by the base. 

 * Corolla not evidently 2-lipped, but almost equally 4-lobed. Stamens erect, distant. 



4. MENTHA. Fertile stamens 4, nearly equal. 



6. LYCOPUS. Fertile stamens 2 ; and often 2 sterile filaments without anthers. 

 * * Corolla more or less 2-lipped ; the tube naked within. 

 - Stamens only 2, distant : no rudiments of the upper pair. 



6. CUNILA. Calyx very hairy in the throat, equally 5-toothed. Corolla small. 



i- - Stamens 4, all with anthers. 



7. HYSSOPUS. Calyx tubular, 15-nerved, naked in the throat, equally 5-toothed. Stamen* 



exserted, diverging. 



8. PYCNANTHEMUM. Calyx ovate or short-tubular, 10- 13-nerved, naked in the throat, 



equally 5-toothed or somewhat 2-lipped. Flowers in dense heads or clusters. 



9. ORIGANUM. Calyx ovate-bell-shaped, hairy in the throat, 13-nerved, 5-toothed. Stamens 



diverging. Flowers spiked, and with large colored bracts. 



10. THYMUS. Calyx ovate, nodding ha fruit, hairy in th throat, 10 - 13 nerved, 2-lipped 

 Stamens distant. Bracts minute. Leaves very small. 



