5. HELICHRYSUM, DeC.
1. Helichrysum prostratum, Hook. fil.; caule decumbente ramoso, foliis (omnibus caulinis) obovatis v. obovato-spathulatis obtusis mucronatis supra arachnoideis subtus ramulisque dense et appresse argenteo-lanatis, involucri squamis interioribus radiantibus albidis scariosis lineari-ligulatis ad apices 2–4-dentatis. (Tab. XXI.)
Hab. Lord Auckland's group and Campbell's Island; confined to rocks at the tops of the hills in the former locality; abundant in the more southern islands, trailing over rocks and banks near the sea. Also found on Mount Egmont, in the Northern Island of New Zealand, at an altitude of 4000 feet, by Dr. Dieffenbach.
This is a graceful and very elegant plant, in many places, and especially on the low grounds of Campbell's Island, covering the banks with its silvery foliage and abundance of flowers. It differs from all other species of the genus Helichrysum, DeC, in the prostrate straggling habit, and in the stems, which are scarcely thicker than a sparrow's quill, being leafy throughout their length, irregularly branched, with the branches divaricating, ascending at their apices, and there bearing the solitary capitula; whereas the Australian species particularly are of an erect growth, those of a more herbaceous habit with larger, as it were radical leaves at the base of the stem. It is however the conical and elongated receptacle that removes this species so far from the 212 described in DeCandolle; a character so evident, and of such importance, as almost to induce me to raise the present plant into a new genus. It is further to be remarked, that though the genus is extensively distributed throughout Australia and Tasmania, where it does not inhabit the mountains, in New Zealand it is represented by the present species alone, which is confined to the most elevated mountains of the Northern Island, and only descends to the lower grounds in a much higher southern and more rigorous latitude.
The leaves are rather scattered upon the stems, ¼–⅓ inch long, elliptical-obovate, produced into a short petiole, rather membranous in texture, silvery white from the dense appressed tomentum beneath, above pale green and opake, covered with scattered silky arachnoid hairs, the margins quite entire. The capitula are ½–¾ of an inch across the ray, pure white or faintly tinged with rose-colour, the outer scales shorter, subulate or lanceolate, cobweby with a loose tomentum. Flowers of the disc very small, almost concealed by the copious white or pale straw-coloured pappus. Tube of the corollas 4-cleft, the segments puberulous externally towards the apex. Anthers biaristate at the base.
Plate XXI. Fig. 1, receptacle and scales of the involucre; fig. 2, inner radiating scales from involucre; fig. 3, a flower; fig. 4, seta of the pappus; fig. 5, flower with the pappus removed; fig. 6, anther; fig. 7, styles:—all magnified.
ASTEROIDEÆ, Less.
6. PLEUROPHYLLUM, Hook. fil.
Capitula multiflora, heterogama; floribus radii 1–3-serialibus ligulatis fœmineis, disci hermaphroditis tubulosis 4–5-dentatis. Involucrum depresso-hemisphæricum, sub 3-seriale, squamis imbricatis lineari-lanceolatis disco brevioribus. Receptaculum planum, nudum, alveolatum, dentatum. Flor. Radii. Corollæ tubo terete
