120 



LABIATAE. 



[Vol. III. 



4. Mentha longifolia (L.) Huds. 

 Horse Mint. (Fig. 3177.) 



Mentha spicala var. longifolia I v . Sp. PI. 576. 1753. 

 Mentha longifolia Huds. Fl. Angl. 221. 1762. 

 Mentha sylveslris L,. Sp. PI. Ed. 2, 804. 1763. 



Perennial by suckers, canescent or puberulent 

 nearly all over; stems mostly erect, branched, or 

 simple, i-2}4 bigh. Leaves lanceolate, ovate- 

 lanceolate, or oblong-lanceolate, sessile, or very 

 short-petioled, acute at the apex, usually 

 rounded at the base, sharply serrate, I'-g long, 



w- 



-\%' wide, sometimes glabrous above; whorls 



5. Mentha rotundifolia (L,.) Huds 



Mentha spicala var. rotundifolia L. Sp. PI. 



576. 1753- 

 Mentha rotundifolia Huds. Fl. Angl. 221. 1762. 



Perennial by leafy stolons, canescent or 

 tomentose-puberulent, somewhat viscid; 

 stems ascending or erect, simple or branch- 

 ed, usually slender, i^-2^ high. Leaves 

 elliptic, or ovate-oblong, short-petioled, or 

 sessile and somewhat clasping y the sub- 

 cordate or rounded base, obtuse at the apex, 

 crenate-serrate with low teeth, i / -2 / long, 

 9 // -i5 // wide, more or less rugose-reticu- 

 lated beneath; whorls of flowers in terminal 

 dense or interrupted spikes which elongate 

 to 2 / -4 / in fruit; bracts lanceolate, acumin- 

 ate, commonly shorter than the flowers; 

 calyx-teeth setaceous, usually about one- 

 half as long as the tube; corolla puberulent. 



In waste places, Maine to North Carolina, 

 Texas and Mexico. Called also Apple Mint, 

 Horse Mint, Wild Mint. July-Sept. 



of flowers in terminal narrow dense or inter- 

 rupted acute spikes, which become 2 / -5 / long in 

 fruit; bracts lanceolate-subulate, the lower equal- 

 ling or longer than the flowers; calyx tomentose 

 or canescent, its teeth subulate, one-half as long 

 as the campanulate tube; corolla puberulent. 



In waste places, Pennsylvania and New Jersey. 

 Naturalized from Europe. Called also Brook- or 

 Fish-Mint, and formerly Water-Mint. July-Oct. 



Round-leaved Mint. (Fig. 3178.) 



6. Mentha alopecuroides Hull. Woolly 



Mint. (Fig. 3179.) 

 Mentha alopecuroides Hull. Brit. Fl. 221. 1799. 



Perennial by suckers, white-woolly; stem 

 stout, leafy, erect or ascending, simple or branch- 

 ed ij4-2, high. Leaves broadly oval, sessile, 

 or partly clasping by a subcordate or rarely 

 rounded base, obtuse at the apex, sharply and 

 rather coarsely serrate, pinnately-veined, the 

 lower 2 / -3 / long, iJ^-2' wide ; spikes rather 

 thick, dense, stout, obtuse, 2 / -3 / long in fruit; 

 bracts lanceolate, shorter than the flowers; calyx- 

 teeth setaceous, one-half as long as the campan- 

 ulate tube, or more; corolla pubescent. 



Along roadsides, southern New York, New Jersey 

 and Pennsylvania to Missouri. Naturalized from 

 Europe. July-Oct. 



