o38 ACANTHUS FAMILY. 



* Twining tropical herbs (or cult, as herbs) , with nearly regular 5-lobed corolla, and 



globular seeds supported by a cartilaginous ring or shallow cup. 



1. THUNBERGIA. Flowers inclosed when in bud by a pair of large ieaf-like bractlets 



borne below the short cup-shaped calyx. Corolla with a mostly somewhat curved 

 tube and an abruptly wide-spreading border of 5 rounded equal lobes, convolute in 

 the bud. Stamens 4, included. Pod globular, tipped with a long and conspicuous 

 flattened beak, 2-4-seeded. Peduncles axillary, 1-flowered. 



* * Erect or spreading ; all the following are herbs, with flat seeds borne on hook-like 



processes (retinaculd) ; calyx i-b-parted, mostly 2-bracted. 

 +- Stamens 4. 



2. ACANTHUS. Corolla of one 3-lobed lip, the upper lip wanting. Stamens with 1- 



celled ciliate anthers. Leaves pinnatifid. Flowers in a spike. 



3. RUELLIA. Corolla funnel-form, with an almost equally 5-lobed spreading border, con- 



volute in the bud. Stamens included ; cells of the anthers parallel. Pod narrow, 

 contracted into a stalk-like base, above 8-12-seeded. 

 +- +- Stamens 2. 



4. DIANTHERA. Corolla 2-lipped, the upper lip erect and notched ; the lower 8-lobed, 



wrinkled or veiny towards the base, spreading. Cells of the anther one below the 

 other, mostly unequal. Pod flattened above, contracted into a stalk-like base, 4- 

 seeded above the middle. 



5. DICLIPTERA. Corolla 2-lipped, the lower Up 3-lobed, the upper 2-cleft or entire ; but 



the flower as it were reversed so that the 3-lobed lip seems to be the upper one. 

 Stamens protruded ; cells of the anther equal, but one placed below the other. Pod 

 2-4-seeded below the middle. 



1. THUNBERGIA. (Named for the Swedish botanical traveler, 

 C. P. Thunberg.} Showy flowers produced all summer. 



T. a/ata, Bojer. So named from its winged petioles ; from Africa ; 

 the one commonly cultivated (as an annual) in many varieties as to size 

 and color of flower, buff, orange, white, etc., usually with blackish-purple 

 eye ; herbage soft-downy or hairy ; leaves between heart-shaped and 

 arrow-shaped. 1J. 



T. fragrans, Roxb. Glabrous on mature parts ; leaves ovate, cordate 

 or hastate at the base, obscurely toothed, or notched towards the base ; 

 flowers fragrant and pure white, one or two in each axil. Greenhouses. 

 India. 2 



2. ACANTHUS. (Old Greek and Latin name, from the word for 

 spine or prickle.} 2Z 



A. mdllis, Linn. One of the classical species, from S. Eu., is occasion- 

 ally cult., not hardy N.; the broad, sinuately and deeply pinnatifid leaves 

 mostly from the root, hardly at all prickly ; flowers on a short scape, 

 dull-colored. 



3. RUELLIA. (Named for the herbalist Euelle,} Ours are wild herbs, 

 chiefly southern, with purple or blue showy flowers, mostly in clusters, 

 produced all summer. 2Z 



R. cili6sa, Pursh. Stems l-4 high ; clothed with soft white hairs, 

 the oval or oblong leaves nearly sessile, pale blue corolla (about 2' long) 

 with slender tube much longer than the inflated upper part and than the 

 bristle-shaped sepals. Dry soil, Mich, and Minn., S. 



R. strfcpens. Linn. Richer soil, from Penn. W. and S. ; smooth or 

 slightly downy, with obovate or oblong leaves (l'-4' long) narrowed into 

 a petiole, and purple-blue corolla (l'-2' long) with tube hardly longer 

 than tbe expanded portion or than the linear-lanceolate sepals. 



