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Journal Number 107
February 2008
THE TYPE LOCALITY
Turakirae Head and Dendrobium lessonii Col.
By Ian St George
In 1882 William Colenso described Dendrobium lessonii [1], a plant he had regarded as different from D. cunninghamii
since 1848. The chief difference between this and D. cunninghamii, he claimed, was the 4-crested labellum
(compared with 5 for D. cunninghamii), along with smaller and fewer flowers, usually only 2 on a peduncle
(not a panicle), different colouring and dwarf terrestrial habit.
In 1906 Thomas Cheeseman wrote, "I cannot separate Mr. Colenso's D. lessonii from the ordinary state of the plant,
even as a variety [2]. Thus Dendrobium lessonii Col. is presently regarded as a synonym for Winika cunninghamii (Lindl.)
M.A. Clem., D.L. Jones & Molloy.
Colenso's description
Dendrobium lessonii, sp. nov.
Plant epiphytal and terrestrial; an erect and pendulous, diffuse slender shrub, often much-branched; branches 6 inches
to 4 feet long, wiry, terete, hard, and brittle; main stems ? of an inch in diameter; colour of stems and branches, some
darkish-umber-brown, and some bright yellow, glossy and horny, ringed with dark scar-like joints, ½-1 inch apart,
under the dry scarious sheathing leaf-bracts, which long remain. Leaves, alternate, ¾-1¼ inch long, 1-2 lines broad,
3-6 lines apart, sub-linear-lanceolate, or sub-ovate-acuminate, broadest near base, sessile, spreading, often falcate
and twisted, coriaceous, semi-rigid, smooth not glossy, pale or yellowish green, margins entire, obscurely 10-nerved,
midrib sunk and obsolete, somewhat concave, suddenly slightly thickened on the under side 1-3 lines from apex, with
a slight corresponding notch in each side, tip obtuse, vaginant, sheaths truncate, longitudinally and regularly striated,
and finely corrugated transversely. Flowers, white, membranaceous, few, scattered, usually 2 (sometimes only 1,
very rarely 3) in a short loose raceme on a stoutish erect peduncle shorter than the leaves, always bursting at a right
angle from the internode in the branchlet, and generally alternating with the leaves, never axillary nor opposite to a leaf;
peduncle glabrous, shining, with 2-3 rather distant sheathing bracts, truncate and obtuse; pedicels, 2-3 lines long,
bracteoles sheathing, acute; perianth nearly 1 inch in diameter, open, expanding, segments of equal lengths; sepals,
ovate-acuminate, 5-nerved, margins entire, upper one the smallest, the 2 lateral ones with a very small round spur at
their base; petals recurved, oblong-ovate, obtuse, with a minute point, margins also entire; labellum 3-lobed, the 2 lateral
lobes small, oblong, obtuse, conniving, margins finely notched; middle lobe large, longer than broad, veined, sub-rotund (or sub-panduriform or broadly obovate), apiculate, margin sub-crenulate with a slight notch on each side, sides conniving,
and 4 longitudinal elevated and shining green (or yellow-green), lamellæ near the base, which are bluntly toothed or crested; column slightly winged near apex, light green; pollen masses yellow. Ovary, 2-3 lines long, green, shining, obscurely striate.
Hab. In forests, Norsewood, Hawke's Bay district, North Island, high up in the forks of pine trees (Podocarpus spicata),
and sometimes on the ground in dry stony hills under Fagus trees, flowering in November; 1879-1882; also among rocks
near the sea at Cape Turakirae (the south head of Palliser Bay), 1845-6: W.C.
Obs. I. - The main branches of this plant are often very regular and spread out flat, bearing a bi-tri-pinnate frond-like
appearance, from the side branchlets of equal length springing at about equal distances from the main stem; a few leaves
on stout and strong young shoots are 1¾ inch long and 2¼ lines broad; the branchlets and peduncles shoot alike erumpent
at right-angles with the stem. Although I have (rarely) seen a raceme bearing 3 flower-buds, I have never seen one with all
three open, the upper one seemed to be abortive; which is also often the case when there are but 2. In some flowers
(on the same plant) the 2 lateral lobes and the extreme base of the middle lobe of the labellum, the throat and column, are
dark pink; in a few others the same parts are slightly speckled with pink.
Obs. II. - I have long known this plant, and, though I early obtained specimens with a few unopened immature flowers from
the rocks at Palliser Bay in 1845, and subsequently assiduously sought for good flowering specimens, I never detected any
such until 1881, when my long previous suspicions of its proving to be distinct from the northern form (D. cunninghamii) were
fully confirmed-I having well known and very often admired and gathered that elegant species in its native forests, where it
is often to be met with. There is much however at first sight, and with only immature flowering specimens, to confound this species with that plant; indeed, it is only by careful examination of several fresh specimens, dissection and comparison, that
their specific differences are perceived, which are chiefly in the labellum, its form and the number and size of its lamellæ
(which in D. cunninghamii are always 5); the colour, too, of its flowers is widely different, these are also smaller and much
fewer in number, usually only 2 on a peduncle, and never assume the panicle form; and also its dwarf terrestrial habit.
Obs. III. - I believe this plant to be identical with the D. biflorum of A. Richard, which was originally discovered by Lesson,
the naturalist of the French expedition under D'Urville, in Tasman's Bay, Cook Straits, in 1827, and published by Lesson and Richard, with a very full description and a folio plate, in 1832; and, therefore, I have great pleasure in naming it after its original discoverer. That New Zealand species, however, was confounded by them with D. biflorum of Swartz, (then a very little
known species, discovered by G. Forster when with Captain Cook in the Society Islands), which species, though very nearly allied, bears only two lamellæ on its labellum. On R. Cunningham re-discovering the Northern New Zealand plant, (which now bears his name,) it was described by Lindley with a plate, as being quite distinct from the D. biflorum of Swartz. Lindley,
however, believed Richard's New Zealand South Island plant to be identical with Cunningham's North Island one, D. cunninghamii. And I think that Sir J. D. Hooker, subsequently adopting Dr. Lindley's opinion, also believed Richard's South Island plant to be
the same as our Northern one; which it certainly closely resembles at first sight in many particulars, although Richard's life-size plate with dissections shows a difference, particularly in its 4-crested labellum. |
Lindley's description of D. cunninghamii accompanied a description and a plate of D. pierardi.
He wrote "basi 5-lamellato".
Several specimens (many from Norsewood) are in Herb. Colenso at WELT [3], among them Colenso's earliest collection,
from Cape Turakirae, sent to Hooker in July 1848, and probably collected when
he was at the Cape in October 1845 on
his biannual walk from Hawkes Bay to Wellington [4].
Colenso rounded Turakirae Head 19-20 April and 27 October 1847, and 28-30 April 1848.
Of those the plant would have
been flowering only in late October 1847, so that seems the likely
collection. His diary entries: 26-27 Oct Uawa.
(village W. side Palliser Bay)
27 Oct … at Waimarara, a small stream, we halted… resuming our journey… over the heavy sands
and craggy rocks,
through the sea and over the cliffs and heights until nearly 9, p.m., when we
reached Pitoone (Petone).
The Turakirae specimen is WELT no. 22584, labelled "1808 D. saxosum"; #1808 is listed in Colenso's letter to Kew of July
to September 1848, with the note, "Dendrobium saxosum, W.C., rocks at Turakirae.
I had long passed this, believing it to be
D. Cunningh., but now I think it to be very distinct". Colenso must have wanted Hooker to accept the name Dendrobium
saxosum Col., and was disappointed.
It was his second attempt to get Hooker to recognise the plant-# 1740 in the same letter is annotated, "Dendrobium,
ditto (ie, clayey hills, Tararua); Epiphytical, on large trees. A sp. apparently near D. biflorum, certainly distinct from
D cunninghamii: - D. Tararuensis, W.C."
He must have gone on a bit about it, for there is an entry in Augustus Hamilton's diary of 1 Jan 1883, "At two I called on
Colenso…. Of the Dendrobium I heard the whole history. He describes it this time in the Transactions.
It differs from the southern? (he means northern - Ed) form by only having four ridges on the lip.
There is a similar species in the North, pink and having five ridges [5].
Hooker's omissions gave Colenso the later opportunity to name the plant for Lesson.
WELT No 24262 is also annotated by Colenso, "Dendrobium - Smaller plant. Leaves few - not striated, sessile,
distant, blunt obscurely - 5-7?-nerved; flower never axillary 1- or 2, peduncle long, bract long, subulate;
see Lindley - ?. c. spn. in bottle from North".
WELT No 52419a has been chosen as the lectotype by Clements et al. No locality is given.
Lesson's illustrations:
Pierre-Adolphe Lesson's watercolour
The engraving made from the drawings
Dumont d'Urville found the plant at Astrolabe Harbour, "parasitic on trees, in NZ woods". If that is the place we now
know as the Astrolabe roadstead, it is 15km north of Motueka, between Adele Is and the coast.
Achille Richard and René-Primavère Lesson's description of the labellum includes the words, "in medio 4-cristatum" (4-crested in the centre) [6]. Hooker's description of Dendrobium cunninghamii, on the other hand, states "disc with five
lamellae", as did Lindley's. Colenso was right so far.
Pierre-Adolphe Lesson's watercolour is shown above (it must be his: he was the brother who accompanied d'Urville
to the South Island). D'Urville recorded the find in his 16 January 1827 diary entry: "Among the parasitic plants,
I noticed some fine Epidendrum or Dendrobium".
The engraving made from the drawings is also shown above. The detail of the flower at lower left shows a central
sulcus in the labellar disc with two ridges to either side: 4 ridges.
What is at the type locality now?
Turakirae Head is at the west end of Palliser Bay, extending down into the windswept Cook Strait.
In the 1840s the track around Cape Turakirae was the main walkway between Wellington and the Wairarapa [7].
Map of Turakirae Head
Its raised beach levels and massive boulders are witness to the elevation of the land in the great earthquake of 1855
(Colenso's original intended epithet saxosum means "of rocky, stony places").
That earthquake effectively ended the use of the track in favour of the Rimutaka Hill route.
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Turakirae Head, looking SE
from the Orongorongo side |
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Entry to the reserve
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The headland is not a hospitable place for orchids. Nonetheless on 19 November the sun was blazing down and a soft sea-breeze cleared the air. Cray floats and seals bobbed in the calm blue sea, and the snow of the Seaward Kaikouras glistened
to the southwest.
Pterostylis banksii in damp spots, stunted Thelymitra longifolia and Microtis unifolia in hollows in the rocks. A fragrant Earina mucronata (I had never smelt it before) was flowering in a crack in one large boulder, and mats of Ichthyostomum pygmaeum covered large areas of others.
Then further round toward the Wairarapa I saw it: a rock as big as a house, virtually roofed with Winika (photo below).
They were short, stunted colonies, yellow-green, but in full flower (photo below right).
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A house-sized rock at Turakirae Head,
thatched with Dendrobium lessonii. |
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The flower of Dendrobium lessonii,
the central
groove on the labellar
disc clearly visible |
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The flowers are exactly the same size and structure as those I have photographed from the South Island and around Wellington and the Wairarapa: the poor habitat has had no effect.
These flowers have a central groove on the labellar disc; they lack the 5th central ridge found in plants from the north, though looking back over my photographs, and others from the collections of Eric Scanlen and the late Bob Goodger, that central ridge
is not completely constant in northern plants either, though all the ridges are more robust and conspicuous than in the southern plants.
Of course, nowadays a lot of northern plants end up in southern collections, and vice versa, so for a populay cultivated plant
like Winika, only wild populations count.
Bruce Irwin's drawings (below) show the five ridges quite clearly,
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Winika cunninghamii - Drawings from Bruce Irwin's
drawings of New Zealand orchids. NZNOG, Wellington, 2007. |
Conclusion
Four ridges or crests or lamellae? or five? A midline groove or a midline crest? Is it a critical point?
Was Colenso right,
and thus should we be calling the southern form "Winika lessonii"?
Or was Cheeseman right, and are these all Winika cunninghamii?
It's a legitimate question. Some molecular biology might be helpful here.
References
1. Colenso W. Descriptions of a few new Indigenous Plants. Trans NZ Inst. 1882; 15: 320.
2. Cheeseman TF. Manual of the New Zealand flora. 1st edition. Wellington, Government Printer, 1906.
3. St George IM. The orchids of Colenso's herbarium at WELT: the work of BG Hamlin. NZNOJ 2001;78: 9-15
4. Colenso W. journals, 1848-51, Typed copy at the Museum of New Zealand, Te Papa Tongarewa.
5. O'Rourke R (ed). A diary of the late Augustus Hamilton. Vol III 1 Jan-28 Apr 1883. Te Papa 2005.
6. Richard A. and Lesson A-P. Essai d'une Flore de la Nouvelle-Zelande. In Dumont d'Urville. Voyage...
De l'Astrolabe. Paris, 1832.
7. Bagnall AG, Petersen GC. William Colenso: his life and journeys. Wellington, AH & AW Reed Ltd. 1948.
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