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§ 2. D i s c o id e u m ; ra d ii corollis abbreviatis, bifidis trifid is v. IriRartitis. (Pachythvix, Hook, fil.)
2. P l e u k o p i i y l l u m crin iferum , H o o k . fil. ; caule to to dense albo-lanato, cap itu lis globosis,
subdiscoide is ligulis b revissimis, re cep tácu lo p lan iu scu lo alveolate, alveolarum m a rg in ib u s su bmemb
ran ac eis d en ta tis. (T a b . X X IV . & X X V .)
H a b . L o rd A u ck la n d ’s g ro u p a n d C am p b ell’s I s la n d ; g en e ra lly in m a rsh y p la ces from th e sea
to an elevation o f 1000 feet, ab u n d a n t. M 'Q u a rrie ’s Is lan d . (Herb. Hook.)
Radix crassa, c.irnosa, subfusiformis, descendens, nigro-fusca, collo fibris crassis elongatis rigidis crisi>ato-
tortuosis fuscis sublignosis (reliquiis foliorum) coronata. Caulis elatus, erectus. crassus, simplex, v. rarius inferne
parce ramosus, 4-6-pedalis, basi unciam diámetro, carnosus. Folia inferiora approximata, multinervia, plicata,
subtus præcipue valde serioea, basi longe sericeo-villosa. nen-is crassis subtus prominentibus fuscis ; marginibus
minute spinuloso-serratis ; radicalia maxima, concava, ovalia, obtusa, sæpe bipedalia, pedem fere lata, basi
attenuata amplexioaulia ; superiora sensim minora, angustiora, apice acuminata, basi magis attenuata : suprema
fere subulata, in bracteis transeuntia. Capitula in racemum spithameum et ultra disposita, nutantla, majuscula,
subglobosa, unciam lata, pedicellata, pedicellis subuncialibus curvatis teretibus rachique dense sericeo-
lanatis. Involucri squamæ lanceolatæ v. subulatæ longissime subarlstato-aeuminatæ, crassæ et coriaceoe, dorso
pilosæ, medio uninerves, marginibus scariosis argute ciliato-seiTatis, apicibus fuscis. Pappus rigidus, subpale-
aceus V. nitidus, recens âavidus, siccitate fuscus apicibus opacis. Fl.. Ran ir sub 3-seriales, ligulati, tubo brevi
terete curvato piloso pllis patentibus mollibus laxis moniliformibus; ligula la te ovata, brevissima, tubo subæqui-
longa, 4-nervis. 3-dentata, v. inæqualiter 2-3-fida, v. tripartita, segmentis linearibus obtusis, marginibus in-
crassatis, luride purpurascens.
A very common and striking plant, often covering a great extent of ground, and forming the larger proportion
of the food of the hogs which now run wild upon the islands of Lord Auckland’s group. It is
indeed so abundant in the marshy spots on the latter islands that these animals frequently Uve entirely amongst it,
especially when it grows near the margins of the woods, where they form broad tracks or runs through the
patches, grubbing up the roots to a great extent, and by trampling down the soft stems and leaves use them as
soft and warm forms to litter in. The leaves are exceedingly handsome, generally two feet long and one or a
little more in breadth, from their concavity holding a considerable quantity of the rain-water or melted snow
which so frequently falls in those latitudes ; in substance they are coriaceous, but not nearly so much so as
m the preceding species, and they are more copiously silky. A full-grown leaf is generally traversed by 30-40
parallel strong nerves, very prominent on the under surface and then dark-coloured and nearly glabrous,
depressed on the upper with longer silky hairs. The intervening parenchymatous substance is traversed by
numerous slender anastomosing veins, beneath densely clothed with a white appressed cottony wool, and
above silky with scattered subarachnoid hairs. The hairs and woolly substance which clothe all the stems, leaves
and pedicels of the capitula are formed of simple terete transparent matted filaments. I do not find .amongst
them any of the short rigid beaded setæ which are intermixed with the softer hairs of the P. speciosum. The
capitula are 15-20 in number ; the lower ones only bracteate with the uppermost leaves, the terminal generally
having a smaller elongate subulate nearly glabrous green bract. The intermediate ones are the most densely
silky on both sides, often so much so as entirely to hide the nerves ; in these, too, the curious but minutely
spinuloso-serrate character of the margin is most easily detected ; the apices of the serratures are callous and
glabrous, almost entirely hid amongst the silky tomentum.
Though this plant is nearly allied to the former species (P . speciosum). and agrees with it in all the most
important characters, they materially differ in the more outward points of resemblance. Indeed I only know
one genus to which the present plant bears any marked similarity in general habit and appearance, and that is
the ArgyroxypMum, DeC. (Prodr. vol. v. p. C68 ; Hook. Ic. Plant, vol. i. p. 75). The mode of growth of these
two plants is the same, and both are natives of Pacific Islands, abounding in peculiarly inclement localities ;
the present being an inhabitant of the Antarctic regions, while the Argyroxyphium is found only on the summits
of tlie highest mountains on the Sandwich islands. Mr. Douglas brought it from the volcano of Mouna
Kaah, which reaches an altitude of 18,400 feet, where it was one of the last plants he met with, and he used
its dead stems for fuel. In the clothing and substance (as far as can be judged from dry specimens) of the
stem, in the disposition of the inflorescence and form of the involucral scales, and in the short Hgulse of the
flowers of the ray, these plants entirely accord : and the lower leaves of the latter, though uniform in size and
shape with the upper, and having the margins quite entire, are always clothed with a similar but more beautiful
and dense silky coat of hairs. On a further examination of the form of the corollas and achænia the analogy
ceases. It must not however be overlooked, th a t the pappus of Pleurophjllum, though composed of setæ (and
not of short paleoe), is of a peculiarly harsh and rigid texture, with each seta flattened and scabrid on the opposite
margins, quite unlike the soft character that organ assumes in most Composite, both showing its affinity to other
Asteroidee, and some approach to the short rigid paleæ of the Sandwich Island plant. Although the Argyro-
xypliium is placed by DeCandolle in Senedonidee, its styles appear .to me to differ in no important particular from
those of the Pleuropkyllum and of other large Asteroid genera. In both these, the styles of the flowers of the
ray are always longer than those of the disc, with the arms also longer, linear, obtuse and flattened, erect or
diverging in most of the tribe, divaricated and inclined to become revolute in Argyroxyphium ; they are invariably
quite smooth throughout, and surrounded wdth a thickened darker-coloured border (the stigmatic series), those
of the corresponding side of each arm meeting at the base. In the flowers of the disc they are shorter, equally
bordered with a thick conspicuous margin, abruptly ceasing at the commencement of a conical, acute, rather
broader apex, which is plane and smooth, or most indistinctly glandular, on the inner surface, but with the
margins and convex back densely studded with elongated papillæ or glands (the pollen collectors) ; these
papillæ, except under a very high pow’er, appear as hairs : the arms have further a strong opake central nerve
in each, meeting and uniting at the base. In Argyroxyphium the conical apices are very short and studded with
long papillæ, whence they appear abrupt, and each of the arms is split into two parallel laminæ, between which
a knife is easily inserted, when the midrib is seen remaining on the inner of the two lamelloe, and the stigmatic
series on the outer. I do not think that in a natural system the two genera now under consideration should
be far separated from one another, or from the following genus Celmisia, Cass.
Though generally so very bulky a plant, tbat an ordinary specimen of the PI. o'iniferum weighs many pounds,
I have seen it so dwarfish upon the mountains as barely to exceed a span in height, with all the leaves lanceolate,
more densely silky, and thus even more nearly resembling Argyroxyphium than it does in its ordinary state.
The masses of curly fibres, which may be taken up in handfulls from the summit of the roots of a common-sized
plant, form a very remarkable character.
P la t e s XXIV. & XXV. Fig. 1, receptacle and portion o f involucre with flower o f ray and disc in situ ; fig. 2,
single scale of the involucre ; fig. 3, alveolæ of the receptacle ; fig. 4, setæ of the pappus ; fig. 5, a corolla
with the ligula 3-partite ; fig. 6, a flower of the ray w ith the ligula 3-toothed ; fig. 7, style from the same ; fig. 8,
front, a n d / / . 9, lateral view o f the achænium ; fig. 10, flower of the disc ; fig. 11, corolla of do. ; fig. 12, stamen,
an d /j-. 13, style from do. :—all magnified.
7. C E L M IS IA , Cass.
Capitulum miiltiflorum, heterogamum ; floribus radii 1-serialibus, ligulatis, foemineis ; disci numerosis, tubulosis,
hermaplu'oditls, 5-clentatis. Involucrum campanulatum, v. depresso-hemispliæricum, plui'iseriale, squamis
elongatis inæqualibus disco paulo longioribus v. subæquîlongis. Receptaculum nudum aut alveolatum, ep.alea-
ceum. latiusculum, plus minusve convexum. F lor. R a d ii. Corolla tubo elongato terete glaberrimo v. piloso pilis
articulatis ; ligula lineari, patente, interdum revoluta, apice subintegra v. 3-dentata, albida. sæpius roseo suffusa.
Stylus teres, gracilis, exsertus, ramis linearibus plus minusve elongatis obtusis y. subacutis, marginibus valde
VOL. I.
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