260 acanthaceje. [Acanthacea. 



Suborder 3. Acanthide^e. — Corolla-lobes imbricate or 2-lipped in the bud, not con- 

 torted Seeds inserted on hooked retinacula. 

 Corolla-lobes 5, nearly equal. 



Corolla with a long tube and spreading lobes. Stamens 4, rarely 2. 



Bracts usually leafy 5. Barleria. 



Corolla campanulate, with a short tube. Stamens 2. Bracts 



very small 13. Codonacanthus. 



Corolla expanded into a single large lower lip. Stamens 4. Leaves 



prickly-toothed 7- Acanthus. 



Corolla 2-lipped, the upper lip notched, the lower 3-lobed or 3-toothed. 



Stamens 4. (Bracts imbricate.) 6. Lepidagathis. 



Stamens 2. 



Anthers 2-celled, oblique, the lower cell mucronate or spurred. 

 Dissepiment remaining attached to the valves of the capsule. 



Anther-cells both with pollen 8. Justicia. 



Lower spurred anther-cell empty. (Flowers small, in cylin- 

 drical spikes.) 9. Rostellaria. 



Dissepiment separating from the valves and curved upwards. 



(Flowers small, in cylindrical or 4-sided spikes) . . . .11. Rungia. 

 Anthers 2-celled, the anthers equal, but one much below the 



other. Dissepiment separating from the valves . . . .12. Dict.iptera. 

 Anthers 1-celled. Flowers contained in calyx-like involucres 10. Hypoestes. 



1. THUNBERGIA, Linn. fil. 



Calyx very short, truncate or toothed, concealed between 2 large bracteoles. 

 Corolla-lobes 5, nearly eqnal, spreading, contorted in the bud. Stamens 4, 

 the cells parallel. Ovules 2 in each cell of the ovaiy. Stigma shortly 2-lobed. 

 Capsule globose and seed-bearing at the base, terminating in a flattened beak. 

 Seeds globular, hollowed out on the inner face and inserted on a cupular ex- 

 pansion of the placenta. — Stems herbaceous, climbing (in some African species 

 dwarf and prostrate). 



A genus limited to tropical Asia and tropical and southern Africa. 



1. T. grandiflora, Roxb. ; Nees in DC. Prod. xi. 54 ; Bot. Reg. t. 495 ; 

 But. Mag. ^.2366. A tall climber, rough with a short pubescence. Leaves 

 broadly cordate, acuminate, angular or broadly 5- or 7-lobed. Flowers large, 

 blue, on axillary peduncles or in a terminal one-sided raceme. Bracteoles 

 1 in. long, often cohering on one edge, so as to resemble a spathaceous calyx. 

 Eeal calyx very short and truncate. Anthers ciliate, one cell of each mucro- 

 nate. 



In a ravine at Say wan, Champion. In the hilly districts of India, from the Nilgherries to 

 Assam, Silhet, Chittagong, and perhaps the Malayan Peninsula ; and frequently cultivated 

 in other parts of India. 



2. HYGROPHILA, Br. 



Sepals 5 or rarely 4, free or more or less united. Corolla 2-lipped, the 

 upper lip notched, the lower 3-lobed, convex in the centre. Stamens 4 ; 

 anther-cells equal and parallel. Style subulate, with a small upper tooth. 

 Ovules several in each cell of the ovaiy. Capsule oblong or linear, seed- 

 bearing along the whole length. Betinacula hooked. — Erect or decumbent 

 herbs. Flowers in sessile axillary clusters. 



A small genus, widely distributed over the tropical and subtropical regions of the New 

 and the Old World. 



