Understood in the wide sense of the "Synopsis Filicum," this is a large genus of 125 species or more, almost cosmopolitan in its distribution. Two of the New Zealand species are endemic, two extend to Australia and the Pacific islands, the remaining two are very widely spread indeed.
| A. Veins free. | |
| Fronds 2–8 ft. or more, deltoid, rigid, coriaceous. Segments ½-1 in. long, decurrent at the base | 1. P. aquilina. |
| Fronds 9–18 in., ovate or ovate-lanceolate, rigid, coriaceous, glandular pubescent. Segments small, 110–¾ in. long, acute | 2. P. scaberula. |
| Fronds 1–3 ft., ovate or deltoid, membranous, glabrous. Segments ½–1½ in. long, obtuse | 3. P. tremula. |
| B. Veins anastomosing. | |
| Fronds 2–4 ft., deltoid, dark-green, 2-pinnate or rarely 3-pinnate. Segments of the pinnules lanceolate or linear-lanceolate, 1–3 in. long, entire or toothed at the tips | 4. P. comans. |
| Fronds 1–3 ft., deltoid, pale-green, 2–4-pinnate. Pinnules often remote, stalked, ovate or deltoid, deeply lobed | 5. P. macilenta. |
| Fronds 2–4 ft., ovate-deltoid to ovate-lanceolate, glaucous, 2–3-pinnate. Pinnæ distant, sessile; pinnules oblong, obtuse, usually entire | 6. P. incisa. |
P. lomarioides, Col. in Trans. N.Z. Inst. xiii. (1880) 380, said to have been collected near Tapuaeharuru, Taupo, is proved by the type specimen in Mr. Colenso's herbarium to be the widely distributed P. cretica, Linn. Although it is just possible that the species may exist near some of the hot springs at Taupo, where other tropical ferns, such as Gleichenia dichotoma, Nephrodium unitum and N. molle are known to grow, still, as the locality has been repeatedly searched without success, the most prudent course is to wait for further evidence before introducing the species into the Flora. The same course must be followed with respect to P. longifolia, Linn., an equally widely spread plant, stated by Mr. Buchanan (Trans. N.Z. Inst. xiv. (1882) 356) to have been gathered at Tarawera, between Napier and Taupo, but of which there are no indigenous specimens in any New Zealand herbarium.
1. P. aquilina, Linn. Sp. Plant. 1533; var. esculenta, Hook. f. Fl. Nov. Zel. ii. 25.—Rhizome stout, as thick as the finger, creeping, much branched, often matted, subterranean, producing numerous scattered fronds. Stipes variable in length, stout, rigid, erect, brown, smooth and shining. Fronds usually from 2–6 ft. long including the stipes, but often taller and sometimes 10–12 ft., broadly deltoid in outline, coriaceous, glabrous or nearly so when mature, usually more or less rusty-pubescent when young, especially on the under-surface, 3–4-pinnate; rhachises grooved above, usually pubescent. Primary pinnæ broad, distant, spreading, the lowest pair the largest and most compound, the upper ones gradually decreasing in size; secondary and tertiary lanceolate, always terminating in a linear obtuse undivided segment. Ultimate segments linear or linear-oblong, decurrent at the base. Veins free, once or twice forked. Sori usually continuous all round the segment, and often extending to the decurrent base. Indusium double, but the
