Manual of the New Zealand Flora/Gesneraceæ
Order LVI. GESNERACEÆ.
Herbs or shrubs. Leaves generally opposite or whorled, simple, entire or toothed; stipules wanting. Flowers usually irregular, hermaphrodite, in axillary or terminal racemes or cymes, or solitary. Calyx inferior or semi-superior, 5-partite; segments valvate. Corolla gamopetalous, usually irregular; tube long or short; limb more or less oblique, lobes 4–5, imbricate. Stamens 2 or 4, inserted on the tube of the corolla; anthers 2-celled. Ovary superior or more rarely inferior, 1-celled; style linear; stigma capitate or 2-lobed; ovules many, anatropous, on two opposite entire or bifid parietal placentas. Fruit capsular or berried, dehiscent or indehiscent. Seeds numerous, small; albumen present or absent; embryo straight.
A tolerably large order, almost wholly confined to tropical regions. Genera 70; species under 800. The order includes many handsome greenhouse plants, especially of the genera Gloxinia and Achimenes, but otherwise its economic properties are unimportant. The single New Zealand genus is endemic.
1. RHABDOTHAMNUS, A. Cunn.
A much-branched shrub; branches spreading, scabrid-pubescent. Leaves opposite. Flowers solitary, axillary. Calyx free, deeply 5-fid; lobes lanceolate, acuminate. Corolla-tube sub-campanulate; limb obscurely 2-lipped; lobes 5, rounded, spreading, nearly equal. Stamens 4 with the rudiment of a fifth, inserted on the corolla-tube below the middle; filaments long, linear, arched; anthers cohering at the apex in a cruciate manner; cells distinct, parallel. Disc small, obscure, annular. Ovary superior, ovoid; style filiform; stigma 2-lobed; ovules numerous, on thick and prominent 2-lobed placentas. Capsule ovoid, acuminate, coriaceous, 2-valved; valves 2-fid, separating from the placentas. Seeds numerous, minute, ovoid.
A monotypic genus confined to the North Island of New Zealand. It is closely allied to the New Caledonian Coronanthera and the Lord Howe Island Negria.
1. R. Solandri, A. Cunn. Precur. n. 385.—Slender, much branched, 2–5 ft. high; branches opposite, terete, everywhere rough with short stiff greyish pubescence. Leaves on slender petioles; blade variable in size, usually ½–1 in. long, but sometimes over 2 in., broadly ovate or orbicular, coarsely toothed, both surfaces rough with short scabrid hairs, dull-green. Flowers handsome, ¾–1 in. long, orange with red stripes; peduncles slender, ½–1½ in. long. Capsule ¼–⅓ in. long, included within the persistent calyx.—Raoul, Choix, 44; Hook. f. Fl. Nov. Zel. i. 186; Handb. N.Z. Fl. 221; C. B. Clarke in D.C. Monog. Phan. v. 166, t. 17. E. scabrosus, Steud. Nom. ed 2, ii. 44-3. Columnea scabrosa, Sol. ex D.C. Prodr. ix. 277.
North Island: Lowland districts from the North Cape southwards to Wellington, but rare and local to the south of the Auckland Province. Sea-level to 2000 ft. Waiuatua; Matata. Flowers most of the year.
For an account of the fertilisation, see a paper by Mr. Petrie in Trans. N.Z. Inst. vol. xxxv. p. 321.