GENUS 32. 



MINT FAMILY. 



141 



32. THYMUS [Tourn.] L. Sp. PI. 590. 1753. 



Perennial herbs, or low shrubby creeping plants, with small mostly entire leaves, and 

 small purple flowers clustered in terminal glomerules, or in the axils of the leaves. Calyx 

 ovoid, villous in the throat, io-13-nerved, 2-lipped, the upper lip erect-spreading, 3-toothed, 

 the lower 2-toothed, its teeth long and slender. Corolla-limb 2-lipped, the upper lip erect, 

 emarginate, the lower spreading, 3-cleft. Stamens 4, more or less didynamous, mostly ex- 

 serted ; anthers 2-celled, the sacs parallel or divergent. Ovary deeply 4-parted ; style 2-clef t 

 at the summit. Nutlets ovoid or oblong, smooth. [Greek, incense.] 



About 50 species, natives of the Old World, mostly European. Type species : Thymus vulgaris L. 



i. Thymus Serpyllum L. Wild or Creeping 

 Thyme. Mother of Thyme. Fig. 3659. 



Thymus Serpyllum L. Sp. PI. 590. 1753. 



Stems more or less pubescent in lines, very slender, 

 procumbent, tough, much branched, 4'-i2' long, com- 

 monly forming dense mats. Leaves oblong or ovate- 

 oblong, petioled, obtuse at the apex, usually narrowed 

 at the base, entire, glabrous, or sometimes ciliate, 2"-s" 

 long ; bracts similar to the leaves, but smaller ; flowers 

 numerous in verticillate clusters crowded in dense short 

 terminal spikes, or also in the upper axils ; calyx dis- 

 tinctly 2-lipped, the tube usually pubescent and the teeth 

 ciliate; corolla longer than the calyx. 



In thickets, woods, and along roadsides, Nova Scotia to 

 southern New York and North Carolina. Naturalized from 

 Europe. Native also of Asia. June-Sept. Old English 

 names, brotherwort, hillwort, penny-mountain, shepherd's- 

 thyme. 



33. KOELLIA Moench, Meth. 407. 1794. 



[BRACHYSTEMON and PYCNANTHEMUM Michx. Fl. Bor. Am. 2 : 5, 7. 1803.] 

 Perennial erect, mostly branched, glabrous cinereous canescent or pubescent herbs, with 

 small white or purple-dotted flowers, in terminal or sometimes also axillary capitate glom- 

 erules or cymose clusters. Calyx ovoid, oblong or tubular, io-13-nerved, equally or more 

 or less unequally 5-toothed, not villous in the throat, the 2 upper teeth sometimes united 

 below. Corolla 2-lipped, the upper lip emarginate or entire, the lower 3-cleft, its lobes 

 obtuse. Stamens 4, didynamous, nearly equal, or the lower pair a little longer; anther-sacs 

 parallel. Ovary deeply 4-parted; style slender. Nutlets smooth, pubescent, or roughened. 

 [Named for J. L. C. Koelle, a German botanist of the eighteenth century.] 



About 17 species, natives of North r America. Besides the following, i occurs in California and 

 several in the Southern States. Type species : Koellia capitata Moench. Mostly very fragrant. 

 Sometimes called Basil, the proper name of Calamint or Ocymum. 



* Leaves prevailingly linear, linear-lanceolate or oblong-lanceolate. 



Calyx-teeth ovate-triangular, acute, one-fourth as long as the tube. i. K. virginiana. 



Calyx-teeth subulate, lance-subulate or bristle-tipped. 



Leaves linear or lanceolate ; calyx-teeth subulate or lanceolate. 



Leaves linear or narrowly linear-lanceolate, entire. 2. K. flexuosa. 



Leaves lanceolate, entire, or usually serrate. 

 Bracts appressed, erect ; clusters dense. 



Hirsute or pilose; leaves mainly entire. 3. K.pilosa. 



Puberulent, short-pubescent, or glabrate ; leaves mostly denticulate. 



4. K. verticillata. 



Bracts spreading; clusters loose. 5. K. clinopodioides. 



Leaves oblong to linear-oblong, obtuse or subacute ; calyx-teeth awn-like. 6. K. hyssopifolia. 



** Leaves prevailingly ovate, ovate-oblong or ovate-lanceolate. 



Calyx-teeth bristle-tipped or subulate. 



Bracts appressed; clusters dense; calyx-teeth bristle-pointed. 

 Bracts spreading ; clusters loose ; calyx-teeth subulate. 

 Calyx-teeth about one-half as long as the tube. 

 Calyx-teeth as long as the tube. 



Calyx-teeth triangular, triangular-lanceolate or lanceolate. 

 Bracts spreading ; clusters loose ; calyx-teeth short. 

 Bracts appressed ; clusters dense. 



Bracts canescent ; leaves firm, acute. 



Bracts ciliate or villous ; leaves membranous, acuminate. 



7. K. aristata. 



8. K. incana. 



g. K. pycnanthemoides. 



10. K. albescens. 



U.K. mutica. 

 12. K. montana. 



