Download New Caledonia - UvA-DARE

BLUMEA
(1977)
23
337—340
Pacific
capsular Myrtaceae
Tristania (New
Caledonia)
Dawson
J.W.
Botany Department,
of
12.
Wellington,
Victoria
University
Zealand.
New
INTRODUCTION
Brown, Aiton’s Hortus Kewensis (2nd Ed.)
Tristania R.
with three
species
have since been added
three original species
Caledonian species
of the
groups
selected the
become
same
to
at
grow
it.
Six
established
was
species
are
the generic
at
decided which
yet been
group.
It has
but ifthe T. laurina
not
currently recognised
on
in
are
groups
of the New
name,
low elevations in scrub and forest
is
group
(1863)
10
not
would
371,
Caledonia where
New
ultrabasic rocks. Species of the
Guinea, Borneo, and
New
these
level. All
Gris, Bull. Soc. Bot. Fr.
et
has shown that the
and further that
groups
original generic
found in Australia,
are
417,
study (Wilson, 1971)
recent
the Tristania laurina
Tristaniopsis Brongniart
name
group
to
a
their separation
warrant
belong
and
three different
to
should retain the
available for
they mostly
genus
belong
different
sufficiently
the
to
(1812)
4
T. laurina, and T. conferta. A number of other species
neriifolia,
T.
—
probably elsewhere
in
Malesia.
DESCRIPTION
Shrubs
smooth;
nate
or
branching
trees;
bud scales
with
a
a
TRISTANIA
monopodial;
leaves
wanting;
2/5 phyllotaxy,
OF
more
(NEW CALEDONIA)
or
less
dark,
stems
young
leptophyllous
to
older
microphyllous,
stems
paler and
pronounced ridge extending from
below each
leaf insertion through several internodes; young parts densely clothed with short
white
reddish
or
simple
to
hairs, older parts glabrous
compound dichasial
branches each terminated by
subtend
(figs.
or
sometimes
as
with
ovary,
brescent
or
orbicular,
style,
to
stamens
to
reduced
to
node (fig.
bud; bracts adnate
except
triangular,
stamens
(figs.
distal parts of
acute;
6,
half their lengths, with
median
stamens
the
7)
in
2—70 stamens
about as long
tip of the
the locules (fig. 6)
or
ovary;
more
stigma small,
to
or
9,
acute
and style,
5,
or
more
the
in
fascicle,
long
as
less
petals,
one to
the petals,
small, dorsifixed, versatile,
Ovary (figs.
as
10),
6,
the longest
placentas apical
less axile (T. glauca, figs.
as
on
they
petal surfaces gla-
per
twice
connective.
convex,
inner
fascicles opposite
5
superior, three-locular; style (figs. 6,9) about as long
into the top of the
axes
stamens
petals (fig. 5)
much shorter; anthers (figs. 8, 9)
at
the
to
i); bracts and bracteoles lanceolate,
pubescent
5,
long,
in upper leaf axils
single flower,
a
hypanthium, filaments, and
white;
single prominent oil gland
superior
set
up
or
outermost
the lateral and inner
next
all parts
sepals (fig. 4)
yellow,
orange,
several series, the
a
the
as
or
remaining pubescent. Inflorescences (fig-*)
dormant vegetative
inner surface
glabrous;
rarely single, fused for
with
far
3). Flowers either with
2,
or
cymes
a
or
alter-
dorsiventral,
9,
in the inner
in the latter
10)
semi-
stamen,
not
angles
case
a
of
stylar
338
BLUMEA
VOL. 23, No. 2,
1977
J.
Figs,
size
—
1
T.
callobuxus.
8.
T.
X15.
Petal; X5.
11.
X15.
17.
—
Fertile
T.
one
Cell
locule; X15.
T.S.
X5.
Embryo; X15.
—
19.
Sterile
—
23.
T. callobuxus:
Placenta
T.S.
14.
—
and
seed; X5.
—
capitulata.
WELTU
(fig.
T.
ovule
L.
group
S.
L.
S.
detail T.S.
T. glauca.
T.S.
inner
T.
into
X10.
9634
—
10.
stylar
tip
of
ventral
is
16.
seeds
stippled; X5.
nat.
5.
L. S.
just
ovary;
above
—
pla-
Dehisced
—
18.
T.
15. T.
capsule;
capitulata.
fertile seed, pigmented cells stippled; X300.
seed; X175.
(Tristania glauca:
(figs.
8,
9),
guillainii: McKee 28014).
McKee
—
22.
McKee 20201,
25585
T.
—
T. glauca. Ovule
13.
T. callobuxus.
—
view; X15.
T. glauca.
canal
—
branch;
Sepal; X5.
integument stippled; X50.
—
Cell detail T.S. testa sterile
cotyledons;
Anther,
locule; X15.
one
at
4. T. callobuxus.
flower; X5.
of fertile
testa
vegetative bud
—
Opening
from
ovule,
capsule, wings
12230, WELTU
19);
glauca.
339
12
callobuxus.
7. T.
ovules removed.
guillainii.
Cell
21.
9.
—
integument stippled; X300.
undehisced
capitulata.
29143, McKee 28863
T.
inner
—
with
Dormant
Bracteole; X3.
L. S. flower; X5.
view; X15.
ovule,
T.
T.
3. T. callobuxus.
into locule
T. callobuxus.
detail
capitulata.
McKee
dorsal
Pacific Capsular Myrtaccae
T. glauca. Inflorescence.
1.
—
T. callobuxus.
6.
T. callobuxus.
seed;
(fig. 21);
—
Anther,
12.
—
Bract; X3.
glauca. View
T.
—
from
group
capitulata.
20.
callobuxus.
callobuxus.
—
centa;
X3.
Tristania R. Br.
—23.
2.
W. Dawson:
T.
McKee
(fig. 17);
T.
—
capitulata.
23839
capitulata:
BLUMEA
340
VOL.
23,
No.
2,
1977
canal is present with an opening into each locule just above the placenta (figs.
pubescent residual
per
locule in
an
14), with
(fig.
(fig.
arc
the
12)
raphe
all
2-layered;
below the placentas
centas
and composed
Fertile
seeds (fig.
teguments;
contents; inner
layer of
outer
outer
i,
plane
2
or
per
outer
heavily thickened
erect,
outer
the
outer
glands
17)
the
splits through
the
fruit (figs.
16,
and
and
the
present in
of each locule
outer
walls
(fig.
16).
in-
and brown
several prismatic crystals
per
cell;
and with the inner and
and the crushed
layers
inner
angle
layer of inner integument colourless.
inner
and inner walls respectively.
oil
the inner
integument and the
(fig. 19) derived from both
tangentially
integument
outer
strongly cordate and overlapping
hypocotyl sheath wanting;
each
mature
thickened
one to
flattened
moderately thickened;
(fig. 21),
the
3 —15
the placenta, anatropous
longitudinal
testa
with
integument
integument brown,
walls of each cell
broad,
(fig. 15)
the
In
locule, winged,
integument with
outer
on
xi),
distinctive central column terminated by the pla-
a
Sterile seeds (fig. 20) consisting of the
inner integument
13)
10,
10); ovules
the vascular strand and
of the ovule
potentially fertile.
result in
of
layer of
inner
between
winged
of axial flower tissue and the inner
o,
layer
outer
circle (T. glauca, fig.
the rim of the hypanthium;
septae
18)
a
transverse
ovules
exserted beyond
capsule
or
strongly
in the median
integument;
nucellus
of the flower free within the stylar canal (fig.
apex
of the
outer
remnants
of the
integument with
Embryo (fig. 22) straight; cotyledons
partly enfolding
each other
(fig. 23);
embryo.
DISCUSSION
The
placing of
(Dawson,
in
a
the
Tristania
Metrosiderinae is
subtribe
1976)
single ring
in
or
a
group
which the New Caledonian
species
to
questionable
as
number of respects
arc
on
the placenta,
—
the
group
differs
from
belong
typical
in the
Metrosideros
alternate leaves, fascicled stamens, few ovules
distinctively winged ovules and seeds,
column in the fruit, and the broad, cordate,
the central
overlapping cotyledons.
REFERENCES
Dawson,
Wilson,
J.
W.
P. G.
of N.S.W.
1976. Blumea
1971. Studies
Sydney.
23: 7
in the
—
11.
systematics
of the
genus
Tristania R. Br. B.Sc. Honours
Thesis.
Univ.