9(7). Anther cells separated on short arms of the connective; corolla violet-blue; 

 sepals uniform 5. Stemodia 



9. Anther cells proximate; corolla yellow or white; sepals usually somewhat 



unequal either in width or length (10) 



10(9). Pedicels bibracteolate at the base; outer sepals much wider than the 



inner; fertile stamens 4; leaf blades pinnately veined 



3. Mecardonia 



10. Pedicels bibracteolate at the apex; sepals nearly equal in width; fertile 



stamens 2; leaf blades palmately veined 4. Gratiola 



11(4). Filaments attached to the base of the corolla, always simple and both 

 pairs antheriferous; capsule loculicidal; seeds more or less reticu- 

 late; sepals united; corolla 1-4 cm. long 8. Mimulus 



11. Filaments attached to corolla for most of their length, the anterior each with 



a projecting knoblike process; capsule not loculicidal; seeds marked 

 with fine transverse lines or smooth; sepals distinct or. united (12) 



12(11). Corolla violet-blue, 5-12 mm. long; the postero-lateral filaments present 

 and antheriferous; capsule 1-6 mm. long, ellipsoid to ovoid, 2- 



celled, septicidal, the platelike septum persisting; sepals 5 



9. Lindernia 



12. Corolla white, 1-2 mm. long; the postero-lateral filaments lacking; capsule 



0.5-1 mm. long, globose, 1 -celled (by lack of septum distally), 

 rupturing irregularly; sepals 4 10. Micranthemum 



13(1). Upper lobes of corolla flattened or widely arched, often spreading; 

 anthers all distinct (14) 



13. Upper lobes of corolla narrowly arched to form a definite galea that encloses 



the anthers; stigmas wholly united; anthers frequently cohering, the 

 pollen being shed in a mass; stamens 4, didynamous; capsules 

 loculicidal; commonly root-parasites (18) 



14(13). Stamens 2, the postero-lateral pair alone developed; corolla 2-5 mm. 

 long, the posterior lobes wholly united; plants not parasitic (15) 



14. Stamens 4, didynamous; corolla 7 mm. long or more, the lobes all evident; 



root-parasites (16) 



15(14). Stems scapelike, the larger leaves in a basal rosette, the cauline leaves 

 reduced and bractlike; flowers in dense cylindric spikelike racemes; 

 corolla bilabiate, cleft nearly to the base 12. Besseya 



15. Stems leafy, the leaves opposite (at least below the inflorescence); flowers 



axillary or in loose racemes; corolla nearly regular, rotate or nearly 

 so 14. Veronica 



16(14). Stamens with only one anther cell developed, the other wholly abortive; 

 corolla salverform, blue to violet-purple or white, the throat very 

 narrow and filled with short stiff hairs; filaments and style less 

 than half the length of the corolla tube; capsule nearly or quite 

 included in the calyx tube; pedicel bibracteolate 17. Buchnera 



16. Stamens with both anther cells equally developed; corolla neither salverform 



nor blue, its throat wide; filaments and style nearly as long as or 

 longer than the corolla tube; capsule partly or nearly wholly 

 exserted from the calyx; pedicel not bracteolate (17) 



17(16). Anther cells glabrous or rarely with a few bristlelike hairs at apex; 

 corolla semirotate, 7-16 mm. long; stigma punctiform or capitate 

 15. Dasistoma 



17. Anther cells villous; corolla semicampanulate, 10-60 mm. long; stigma 



somewhat elongate 16. Agalinis 



1457 



