MONOPETALOUS EXOGENOUS PLANTS. 393 



** Stems terete, mcculent^ creeping; leaves ovate or roundish, entire; exterior calyx- 

 lobes cordate or ovale ; peduncles 'i-bracted at the apex. 



H. AMPLEXiCAULis, Pursli. Stem villous, ascending 

 from a creeping base ; leaves smootliish, ovate, cordate and 

 clasping, obtuse ; peduiicles shorter than the flowers ; ex- 

 terior calyx-lobes cordate ; base of the ovary surrounded by 

 a 12-toothed disk. (H. rotundifolia, Ell., not of Pursh.) 

 Flotvering stems 6-8' high; leaves 1^' long, crowded; 

 flowers blue ; pla7it odorous ; perennial. 



GKATIOLA, L. Hedge-hyssop. 



Calyx 5-parted, the lobes nearly equal, narrow ; corolla 

 bilaliiate, with the upper lip entire or emarginate, the 

 lower 3-cleft ; fertile stamens 2, included, the anterior ones 

 sterile or wanting ; stigma 2-lipped ; capsule 4-valved, 

 many-seeded. — Low perennial herbs, with opposite leaves, 

 and solitary axillary wliite or ^^ eWovf floiuers ; calyx mostly 

 2-bracted. 



* Connective of the anthers dilated, the cells transverse; stems tender ; flowers 



peduncled. 

 t Sterile stamens minute or none. 



G. ViRGiNiANA, L. Stem branching from the base, 

 glandular-pubescent above ; leaves lanceolate, acute, spar- 

 ingly serrate, sessile, the lower ones narrowed at the base ; 

 pedu7icles slender, the .upper ones longer than the leaves ; 

 corolla white, with the yellowish tube twice as long as the 

 calyx ; capsule ovate, acute. Stem 6'-12' high ; leaves 1' 

 long; corolla 5"-6" long, hairy within. 



G. Floiiidana, Nutt. Stem simple or branched, smooth ; 

 leaves lanceolate or oblong, obtuse, entire or nearly so, nar- 

 rowed at the base, sessile, the low^est slightly petioled ; joe- 

 duncles filiform, longer than the leaves ; lobes of the corol- 

 la emarginate, white ; the slender yellowish tube three 

 times as long as the calyx. Stem 1° high ; leaves 1' long ; 

 corolla 8" long ; capsule globose. 



17* 



