388 CH. ACANTHAcaffi. (C. B. Clarke.) 



Tribe 1. Thunberg'ieae. Scandent or twining. Co ?ya; minute, annular 

 or 10-15-toothed. Corolla-lobes twisted in bud. Ovules 2 in each cell, 

 collateral. Capsule beaked ; retinacula . . . 1. Thunbebgia. 



Tribe 2. Nelsonleee. Corolla-lobes imbricate in bud. Ovules many, 

 superimposed in two rows in each cell. Seeds small, seated on minute 

 papillae, not on hard retinacula, obscurely aJbuminons. 



Calyx 4!-partite. Stamens 2. Bracts rigid, imbricate . 2. Ezytsabia. 



Calyx 4-partite, Stamens 2. Bracts herbaceous . . 3. Nblsokia. 



Calyx S-partite. Stamens 4 4. Ebebuaieba. 



Calyx S-partite. Stamens 2, exserted 5. OPHioBBmziFHTixTru. 



Tribe 3. Ruellieae. CaroZZa-7o5e« twisted to the left in bnd. Seeds on 

 retinacula. Sepals 5, or 4 with one larger. Anthers usually 2-celled ; cells 

 parallel or one a little below the other. St^/le 2-fid, one lobe often 

 suppressed. 



Subtribe 1. Poltspebmile. Ovule-t 3-12 in each cell. Capsule normally 

 6- or more-seeded. 



* Corolla distinctly 2-lipped. 



Lower leaves often toothed or pinnatifid. Flowers 



axillary, sessile. Betinacula scarcely hooked ... 6. CiS,l>ASTBSSA. 

 Leaves entire. Flowers axillary, subsessile. Ketinacola 



hooked 7. Htgbophila. 



Cymes elongate. Branches sympodal 8. Nomapsila. 



** Corolla subequally 5-lobed. 



Bracteoles large. Stamens muticous. Capsule clavate. 



Base of capsule solid 10. Ruellia. 



Cymes elongate with sympodal branches. Anther-cells 



mucronate at base 11. EoHnfACAifTHUS. 



Flower-clusters separate on the cyme-branches. Con- 

 nective excurrent at tip. Capsule seed-bearing 



from the base 17. yEcHUANTHEBA. 



Flowers capitate or axillary, subsessile. Bracteoles 



small, narrow, or 0. Capsule seed-bearing Irom the 



base .... 15. HsMiaBAPHis. 



Flowers clustered at the nodes of the almost leafless 



branches in terminal panicles. Stamens, muticous. 



Capsule seed-bearing from the base . .... 16. Stenosiphoitium. 



Subtribe 2. TEiaASPEBio:^. Ovules 2 in each cell. Capsule 4- or fewer- 

 seeded. 



* PlacenteB not rising elastically from the base of the capsule (except in 

 a few Strobilanthes). 



Corolla subequally 5-lobed. Stamens 4 or 2 ; anthers 



muticous 18. Stbobilanthes. 



Corolla large, deeply 2-lipped. Stamens 4; anthers 



muticous . 19. CAiACAiTTHrs. 



Corolla somewhat 2-lippea. Stamens 4 ; anthers 



minutely mneronate at base 9. Caiophabes. 



rolla-tuba very long, linear; lobes subequal. Stamens 2 14. D^SDALACAifTHirs. 



** PlaeentcB rising elastically from the base of the ripe capsule. 



Corolla small. Stamens 4. Bracteoles 13. Phayxopsis. 



Stamens 4 Bracteoles very large, reticulately nerved . 12. Petalidiuk, 



