As defined by Hooker and Bentham in the "Genera Plantarum," this is a large and heteromorphous order, comprising between 80 and 90 genera and nearly 700 species. Most of the species are either tropical or inhabit South Africa or Australia. They are comparatively rare in the north temperate zone. The chief characteristic of the order is the presence of an essential oil, which is usually abundant in the leaves and young growing parts, often giving them an aromatic odour and bitter or pungent taste. The orange, lemon, citron, lime, &c., are the chief economic species. The two New Zealand genera are also found in Australia, and Melicope extends into the Pacific islands as well.
| Leaves simple, petiole terete. Flowers 5-merous | 1. Phebalium. |
| Leaves compound, or if simple with the petioles winged. Flowers 4-merous | 2. Melicope. |
1. PHEBALIUM, Vent.
Shrubs. Leaves alternate, simple, entire or slightly toothed, pellucid-dotted. Flowers usually in axillary or terminal corymbs, rarely solitary. Calyx small, 5-lobed or -partite. Petals 5, imbricate or valvate. Stamens 8–10, longer or shorter than the petals; filaments filiform, glabrous. Ovary 2–5-partite almost to the base; style simple; stigma small, capitellate; ovules 2 in each cell, superposed. Cocci 2–5, truncate or rostrate; endocarp cartilaginous and separating elastically. Seeds usually solitary.
A genus of 28 species, all of which are confined to Australia with the exception of the present one, which is endemic in New Zealand.
1. P. nudum, Hook. Ic. Plant. t. 568.—A graceful much-branched perfectly glabrous shrub 4–12 ft. high; branchlets slender, with reddish bark. Leaves alternate, 1–1½ in. long, linear-oblong or narrow oblong-lanceolate, coriaceous, obtuse, obscurely crenate, narrowed into short petioles or almost sessile, pellucid-dotted. Flowers ⅓ in. diam., white, fragrant, in terminal many-flowered corymbs; pedicels short, scurfy. Calyx very small, with 5 broad lobes. Petals 5, lanceolate or linear, obtuse; margins involute. Stamens much longer than the petals. Cocci 1–4, but usually only 1 or 2 ripen, obtusely rhomboid, wrinkled, splitting into 2 valves.—Raoul, Choix, 48; Hook. f. FI. Nov. Zel. i. 44; Handb. N.Z. Fl. 39; Kirk, Students' Fl. 85.
North Island: Hilly forests from Kaitaia southwards to the Thames River, ascending to 2.500 ft. Mairehau. October–December.
Highly aromatic in all its parts. The flowers have been used for the extraction of a perfume.
2. MELICOPE, Forst.
Trees or shrubs. Leaves opposite or alternate, simple or 3-foliolate, rarely pinnate, pellucid-dotted. Flowers usually small, often unisexual, in axillary or terminal few- or many-flowered cymes or panicles. Sepals 4. Petals 4, valvate or imbricate, with inflexed tips. Stamens 8, inserted at the base of the disc; filaments subulate. Ovary 4-lobed almost to the base, 4-celled; style single
