The Botany of the Antarctic Voyage/Part I/Ranunculaceae

From Wikisource
Jump to navigation Jump to search
2567158The Botany of the Antarctic Voyage, Part I — I. RanunculaceæJoseph Dalton Hooker


1. Ranunculus (Hecatonia) pinguis, Hook. fil.; acaulis, carnosus, pilosus, foliis omnibus radicalibus longe petiolatis reniformi-rotundatis crenato-lobatis, petiolis basi late vaginantibus, scapis crassis nudis v. 1–2-bracteatis folia æquantibus unifloris, sepalis 5–8 calyce brevioribus obovato-cuneatis v. linearibus, nectariis 3 quandoque nullis v. obsoletis, carpellis numerosissimis in capitulum globosum arcte congestis vix compressis utrinque subalatis dorsoque carinatis stylo valido recto bialato apice sæpe uncinato terminatis. (Tab. I.)

Var. β. pilosus; minor, petiolis foliis scapis calycibusque magis pilosis, petalis linearibus sepalis ⅓ brevioribus, nectariis 3 valde distinctis.

Var. γ. rhombifolius; minor, foliis subrotundo-rhombeis 3–5-fidis segmentis subacutis crenato-dentatis v. integris.

Hab. Lord Auckland's group.α and β in boggy places on the hills, alt. 1000 feet; and from the sea to the mountain tops, alt. 1200 feet, in Campbell's Island.γ. Rocky places in Lord Auckland's group, alt. 1200 feet, rare.

Radix perennis, crassa, subpræmorsa, magis minusve elongata, fibros pallidos carnosos simplices, superne præcipue, emittens. Folia 1–2 unc. longa, 2–3 lata, omnia radicalia, patentia v. erecto-patentia, carnosula, crassa, pilosa (pilis deciduis), longe petiolata, reniformi-rotundata, radiatim venosa, basi lata subincurva, vel subrhomboidea, omnia pluri-lobata, lobis rotundatis magis minusve obtusis integris v. crenatis. Petioli 1–3 unciales, folio longiores, semiteretes, pilosi, basi latissime vaginati, vaginis striatis nervosis extus sæpe rigide fibrosis e reliquiis persistentibus vaginarum vetustarum, margine membranaceis. Scapi solitarii v. bini, rarius plures, erecti, crassi, foliis vix longiores, teretes, pilosi, 1- v. rarissime 2-flori, nudi v. 1–2-bracteati, bractea elongato-cuneata integra v. obtuse 1–2-dentata. Flos majusculus, unciam latus. Calyx 5- rarius 6-sepalus, sepalis patentibus, ovalibus, submembranaceis, purpureo-tinctis. Petala flava, purpureo-venosa, numero varia, 5–8–10, obovato-cuneata, v. lineari-spathulata, inæqualia, calyce breviora, medio nectarifera, nectariis e glandulis 3 depressis marginatis, in totidem nervos sitis. Stamina plurima; filamentis latis; antheris ovalibus obtusis. Carpella numerosissima, in capitulum globosum magnitudine Coryli Avellanæ nucis, glaberrima, lævia, ovata, nec compressa, dorso carinatis, lateribus alato-marginatis, alis ad apicem styli stricti uncinati rective decurrentibus.

A very handsome species, and quite distinct from any with which I am acquainted. It possesses, however, several of the peculiarities of other Ranunculi from the mountains of South America and the high southern latitudes, particularly in the variable form and number of the petals. In its succulent habit and undivided leaves it has an affinity with R. Cymbalaria, but is perhaps most nearly allied to R. nivicola (Hook. Ic. Pl. t. 571–2); especially as in one of our specimens the scape is bifid, 2-flowered, and bearing a large cauline leaf, thus showing a disposition in the plant to become caulescent. In the less divided foliage, shape of the petals, &c., it widely differs from that species, and more particularly in the curious nectaries which are only observable in the var. β, becoming evanescent in the larger and common state of the plant. Here they are large, and situated each about the middle of one of the three principal nerves, which seems to branch into three, the middle branch being continued through the nectary, while the lateral ones are thickened and run round its edge, all three uniting again at its summit. This circumstance may however be only caused by the thickened margin of the fovea, as the nerves do not appear branched in the petals of α, nor in those of intermediate states, where the nectaries are only perceptible as opake spots. These singular nectaries are also common to another scapigerous single-flowered species, the R. Gunnianus of Tasmania (Hook. Journ. Bot. vol. i. p. 244. t. 133), a plant which has also compressed or 2-winged styles.

Plate I. Fig. 1, sepal; fig. 2 & fig. 3, petals; fig. 4, petal of var. β; fig. 5, stamen; fig. 6, ovarium; fig. 7, the same cut open:—all magnified.

2. Ranunculus (Hecatonia) acaulis, Banks et Sol.; pusillus, glaberrimus, sarmentosus, foliis omnibus radicalibus longe petiolatis cordatis ternatim sectis, lobis seu foliolis subpetiolulatis, obtusis, intermedio integro v. trifido, lateralibus integris v. inæqualiter bifidis, scapis solitariis petiolo brevioribus, sepalis 3–5 ovato-rotundatis, petalis 6–8 flavis late spathulatis obtusis calyce duplo longioribus medio squamuloso-nectariferis, capitulo globoso, carpellis paucis (5–7) ovatis gibbosis lævibus stylo recto brevi subulato terminatis. (Tab. II.)—Banks et Sol. MSS. in Herb. Mus. Brit. DeC. Prodr. vol. i. p. 34. A. Cunn. Prodr. Fl. Nov. Zeal. in Ann. Nat. Hist. vol. iv. p. 258.

Hab. Lord Auckland's group; moist places near the sea.

These specimens entirely agree with others gathered in the Bay of Islands, New Zealand: the plant apparently prefers, and is perhaps confined to, the immediate neighbourhood of the sea, and in this meridian has a range of 16 degrees of latitude at the level of the ocean. The only species to which it has any affinity is the R. stenopetalus, Hook. (Ic. Plant. t. 677), from Chili, to which it is very nearly allied; the difference in the comparative breadth of the petals being almost the only one I have been able to detect. The situation of the nectary on the petals near their middle is common to a large proportion of the species of this genus in the southern hemisphere, but very rare in those of the northern; the R. parviflorus being perhaps the only British one in which it is inserted at a considerable distance from their base. The foliage of this plant is sufficiently accurately described by DeCandolle from Sir Joseph Banks's New Zealand specimens, but the corolla requires some correction, and the fruit was unknown to that author. The calyx consists of from 3–5 membranous, very concave, deciduous sepals. Petals narrow, variable in number, about twice as long as the sepals, bright yellow, 1½ line long, spreading and horizontal in the expanded flower during the day, 3-nerved; nectary conspicuous, sunk, and covered with a closely appressed scale, forming together a deep fovea, opening upwards, placed on the middle of the petal and resembling the fructification of some Davallia. Filaments short, linear-subulate. Anthers broadly oblong. Ovaries about 15, some abortive, gibbous at the base, with a curved falcate style. Carpels forming globose heads, few in number, 5–8 or 10, rather large, compressed, especially towards the axis of the receptacle; the style straight or curved, very short or longer and subulate.

Plate II. Fig. 1, bud; fig. 2, flower; fig. 3, sepal; fig. 4, petals; fig. 5, stamen; fig. 6, ovarium; fig. 7, head of carpels; fig. 8, carpel removed; fig. 9, vertical section of the same; fig. 10, lateral; and fig. 11, front view of seed:—all more or less magnified.

3. Ranunculus (Hecatonia) subscaposus, Hook. fil.; totus pilis subrigidis appressis fulvis hispido-pubescens, foliis plerisque radicalibus longissime petiolatis deltoideo-cordatis profunde tripartitis lobis late cuneatis inaequaliter 3–7-fidis segmentis acutis, scapis folio brevioribus unifloris 1–3-phyllis superne incrassatis et dense pilosis, petalis 5 calyce brevioribus obovato-oblongis infra medium squamuloso-neetariferis.—Hook. Ic. Plant. vol. viii. ined.

Hab. Campbell's Island; by the margins of rivulets in the woods, D. Lyall, Esq.

This plant I never saw growing; it was detected by my friend Mr. Lyall. In general appearance it very closely resembles the R. lappaceus, Sm., of Tasmania and the northern parts of New Zealand, a species which varies much in size, in the form of the leaves, and in the nature of the pubescence. The R. subscaposus is more slender in habit, with the hairs always closely appressed and of a tawny yellow colour; but the most important distinction lies in the form and size of the petals, which in R. lappaceus are much larger than the calyx and very broadly obovato-cuneate, with a large triangular fleshy nectary at the very base; but in this plant they are smaller, of a very different shape, and the nectary consists of a minute flat round scale placed a little below the middle. The petioles are nearly a span long; the leaves about an inch in length and somewhat more in width.