Dictyogens in every point of view, except that it possesses an equally continuous and denned zone of woody tissue, within the cuticle, separated from the latter by a zone of parenchyma, and enclosing a mass of pure pith.
The Philesia buxifolia is among the handsomest plants of the Antarctic American Flora ; it occurs along the coast from the Strait of Magalhaens to Yaldivia ; to the northward of which, between Valdivia and Concepciou, it is replaced by the Lapageria rosea.
LIII. ASTELIEÆ, Brongniart.
1. ASTELIA, Banks et Sol.
1. Astelia pumilo, Brown, Prodr. p. 291. Gaud, in Ann. Sc. Nat. vol. v. p. 100. et in Freyc. Toy. Bot. p. 132. B'Urv. in Mem. Soc. Linn. Paris, vol. iv. p. 603. Ft. Antarct. vol. i. p. 76. Melanthium pumiluni, Forst. Comm. Goett. vol. ix. p. 30. t. 6. Banks et Sol. MS. in Mm, Banks, cum icone. Funkia Magellanica, JFilld. May. Naturf. Fr. vol. ii. p. 19. (Tab. CXXVII).
Hab. South Chili, from the Chonos Archipelago to Cape Horn, very abundant on the hills and in exposed places, Commerson, and all future voyagers; Falkland Islands, Gaudichavd, fyc.
Under the description of A. linearis, in the first part of this volume, I mentioned that the placentation varies in the different species of this genus. In the majority, the ovules are numerous and arranged in two lines upon parietal placenta? ; in one the seeds are numerous and pendent from the summit of a one-celled berry, whose dissepiments have probably been absorbed ; a third form presents a three-celled ovarium, with several ovules pendulous from the summit of each cell; a fourth has a three- to six-celled subcapsular fruit, with a few pendulous seeds in each cell; while the present plant offers a fifth modification, for its placentation is decidedly axile, and the ovules are arranged in two rows along the inner angle of each of the three cells. This arises from the perfect consolidation of the carpels in a young state, when the edges of each carpellary leaf are so inflected as to meet in the axis of the pistil, where a triangular longitudinal cavity is often left (see fig. 5 of Plate CXXVII.). At an early period the cavity of each capsule is not apparent, the ovules being imbedded in a cellular mass, which in this species retires from between and around the ripening seeds, leaving a distinct cavity as the fruit advances to maturity, but in some others remains, partly attached to the placenta? and seeds, as a mucilaginous or gummy mass. At no time is the fruit of this plant truly even sub-capsular, its walls are always fleshy, and no trace of dehiscence can be seen along the furrows of each carpel, from which the seeds escape by the decay of the pericarp.
I have followed M. Brongniart in placing this genus by itself in a natural group, whose nearest affinities I have indicated in the first part of this work.
The Astelia piimila is a most abundant Fuegian and Falkland Island plant, forming, with the Caltha appendiculata especially, a large proportion of the peat in those countries. Its flowers are inconspicuous, and have a faintly sweet smell.
Plate CXXVII. Fig. 1, three-flowered peduncle, bract and flower; fig. 2, flower removed; fig. 3, pollen; fig. 4, ovarium; fig. 5, transverse section of the same; fig. 6 and 7, ovules; fig. 8, ripe fruit; fig. 9, transverse section of ditto; fig. 10, ripe seed; fig. 11, the same with the outer osseous integument removed; fig. 12, the same, cut longitudinally; fig. 13, embryo:—all magnified.
LIV. JUNCEÆ, DC.
1. ROSTKOVIA, Desv.
1. Rostkovia grandifiora, Hook, fil.; in Fl. Antaret. vol. i. p. S2. Marsippospermum calyculatum, Best. Bot. Joum. vol. i. p. 330. M. grandifiorum, Hook. Ic. Plant, t. 533. Juncus grandillorus, Linn, fil,
