388 FLOllA OF TEXAS. 



or bilabiate, the lobes imbricated in the bud ; fertile sta- 

 mens 4 (sometimes 2, rarely 5), mostly didynamous, in- 

 serted on the tube of the corolla ; anther-cells often separate, 

 opening lengthwise; ovary free, 2-celled, many-ovuled ; 

 placentcB CQwtvaX', style simple or 2-cleft ; capsule 2-celled, 

 many- (rarely 1-few) -seeded; seeds anatropous; embryo 

 small, in copious albumen. 



SYNOPSIS. 



Tipper lip of the corolla exterior in the bud (exce2)t Mimulus). Capsule commmdy 

 septicidally dehiscent. 



* Stamens 5, all perfect. Corolla regular. 



Corolla wheel-shaped. Filaments, or part of them, bearded. Leaves alternate. 



Yerbascdm. 



** Fertile stamens 4, the fifth sterile., or I'udimentary. Flowers cymose. Leaves 



opposite. 



Corolla globose or oblong ; four of the lobes short and erect. Fifth stamen scale- 

 like SCROPIIULARIA. 



Corolla tubular, inflated, contracted at the throat. Fifth stamen shorter than the 



others. Seeds winged •. Chelone. 



Corolla dilated.upward. Fifth stamen as long as the others. Seeds wingless. 



Pe^tstemon. 



*** Fertile stamens 4 ; sterile ones none. Flowers axillary or racemed. 



Corolla spuj'red at the base. Capsules toothed at the apex Lenaria. 



large. Calyx tubular, 5-angled, 5-toothed MiMULue. 



• short. 6-parted ; the three outer lobes much larger HtRPESTis. 



**** Fertile stamens 2 / sterile ones 2 or none. 



Calyx b-parted. Sterile filaments entire, included. Capsule ovate or globose. 



Gratiola. 



Cahjx 5-parted. Sterile flliments 2-cleft, exserted. Capsule oblong Ilysanthhs. 



Cahjx ^-parted. A scale-like appendage below the filaments Micranthemum. 



Upper lip of the corolla inteHor in the bud. Capsule commonly locuUcidally de- 

 hiscent. 



* Corolla regular or slightly 2-lipped ; the lobes nearly equal. 

 t Stamens 2, distant. Capsule mostly obcordate. 

 Style simple. Flowers in leafy racemes or spikes Veronica. 



