388 cix. ACANTHACE^;. (C. B. Clarke.) 



Tribe 1. Thunberg-iese. Scandent or twining. Calyx minute, annular 

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

 collateral. Capsule beaked ; retinacula ... 1. THUNBEEGIA. 



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

 superimposed in two rows in each cell. Seeds small, seated 0n minute 

 papillae, not on hard retinacula, obscurely albuminous. 



Calyx 4-partite. Stamens 2. Bracts rigid, imbricate . 2. ELYTEAEIA. 



Calyx 4-partite. Stamens 2. Bracts herbaceous . . 3. NELSONIA. 



Calyx 5-partite. Stamens 4 4. EBEEMAIEEA. 



Calyx 5-partite. Stamens 2, exserted 5. OPHIOBBHIZIPHYLLTJM. 



Tribe 3. Ruellieae. Corolla-lobes twisted to the left in bud. Seeds on 

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

 oarallel or one a little below the other. Style 2-fid, one lobe often 

 suppressed. 



Subtribe 1. POLYSPERME^E. Ovules 3-12 in each cell. Capsule normally 

 6- or more-seeded. 



* Corolla distinctly 2-lipped. 



Lower leaves often toothed or pinnatifid. Flowers 



axillary, sessile. Retinacula scarcely hooked ... 6. CABDANTHEBA. 

 Leaves entire. Flowers axillary, subsessile. Retinacula 



hooked 7. HYGEOPHILA. 



Cymes elongate. Branches sympodal 8. NOMAPHILA. 



** Corolla subequally 5-lobed. 



Bracteoles large. Stamens muticous. Capsule clavate. 



Base of capsule solid . . 10. RUELLIA. 



Cymes elongate with sympodal branches. Anther-cells 



mucronate/fct base /V- vwWi v *-w 11. ECHINACANTHTTS. 



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

 nective excurrent at tip. Capsule seed-bearing 



from the base 17. ^ECHMANTHEEA. 



Flowers capitate or axillary, subsessile. Bracteoles 



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



base 15. HEMIGEAPHIS. 



Flowers clustered at the nodes of the almost leafless 



branches in terminal panicles. Stamens muticous. 



Capsule seed-bearing from the base 16. STENOSIPHONIUM. 



Subtribe 2. TETRASPERME.E. Ovules 2 in each cell. Capsule 4- or fewer- 

 seeded. 



* Placenta 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. CALACANTHTJS. 



Corolla somewhat 2-lipped. Stamens 4 ; anthers 



minutely mucronate at base 9. CALOPHANES. 



rolla-tube very long, linear; lobes subequal. Stamens 2 14. D^DALACANTHUS. 



** Placentae, rising elastically from the base of the ripe capsule. 



Corolla small. Stamens 4. Bracteoles - 13. PHATLOPSIS. 



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



