242 
obclavate: club shaped and attached at the narrow 
end. 
obconic: conical but attached at the narrow end. 
obcordate: cordate but attached at the narrow end. 
obdeltoid: deltoid but attached at the narrow end. 
oblanceolate: lanceolate but attached at the narrow 
end (Fig. 80). 
obloid: of a solid body with an oblong section or 
outline. 
oblong: rectangular but with rounded ends, length to 
breadth ratio c. 2:1 (Fig. 80). 
obovate: ovate but attached at the narrow end (Fig. 
80). 
obovoid: ovoid but attached at the narrow end. 
obpyriform: pear-shaped and attached at the broad 
end. 
obtuse: blunt, terminating in a broad angle (Fig. 80). 
ochrea: sheathing leaf-base of members of 
Polygonaceae, possibly a pair of fused stipules. 
operculum: a cap, e.g. in Eucalyptus flowers a 
compound structure of perianth parts (Fig. 48a). 
opposite: where two organs arise from the same node 
on opposite sides of the axis (Fig. 80). 
orbicular: circular (Fig. 80). 
ovary: part of the gynoecium which encloses the 
ovules (Fig. 79). 
ovate: egg-shaped in outline (Fig. 80). 
ovoid: of a solid body with an ovate section or ovate 
in outline. 
ovule: organ which after fertilization develops into 
the seed (Fig. 15). 
palmate: divided fan-wise or like the fingers of a 
flattened hand (Fig. 80). 
panicle: an inflorescence with compound branching, 
hence paniculate (Figs. 48,79). 
pantropical: occurring throughout the tropics. 
papillose: with minute, rounded, elongated 
projections on the surface. 
parietal placentation: in which two or more 
placentas develop on the wall of a uniloculate 
ovary (Fig. 79). 
paripinnate: of compound leaves lacking a terminal 
leaflet (Fig. 80). 
patent: spreading, diverging from the axis at 90 
degrees. 
pectinate: divided like a comb, into evenly spaced 
narrow segments. 
pedicel: stalk of a flower (Fig. 79). 
pellucid: translucent. 
peltate: of a structure with axis inserted on the lower 
surface, e.g. of a petiole on a leaf (Fig. 80). 
penicillate: like a tuft of hairs, as seen in Urtica 
(nettle), where the stigma consists of a number 
of hair-like branches. 
penninerved: pinnately nerved. 
perennial: with a life-span of more than one year. 
perfoliate: of a sessile leaf or bract where the base 
extends around the leaf, so that the stem appears 
to pass through the blade. 
perianth: the floral envelope, usually consisting of 
two whorls, the calyx and corolla; specifically 
where the segments (tepals) of the perianth are 
much alike but in whorls, (e.g. Euphorbiaceae, 
Liliaceae) or quite similar and in a single whorl, 
(e.g. Chenopodiaceae). 
pericarp: the outer wall of a fruit, which develops 
from the wall of the ovary and composed of three 
layers - the exocarp, mesocarp and endocarp. 
perigynous: when the sepals, petals, and stamens 
are inserted round the superior ovary on the 
cup-like or tubular torus or receptacle; the 
stamens also appear perigynous when inserted 
on the corolla. 
persistent: e.g. of floral parts not shed after flowering. 
petal: a member of the corolla (Fig. 79). 
petaloid: having the appearance of a petal. 
petiole: part of a leaf (the stalk) which bears a leaf 
blade (lamina), at the point of attachment to the 
branchlet usually ending in a swelling (Fig. 80). 
petiolule: the stalk of a leaflet within a compound 
leaf. 
phyllanthoid: of leaves distichous on lateral 
branchlets, giving the appearance of pinnate 
leaves. 
phyllode: a leaf-like petiole or rachis (often broad 
and flattened), taking the place of leaves in most 
Australian species of Acacia (Fig. 1). 
pilose: with soft, clearly separated but not sparse hairs. 
pinna: pl. pinnae; the primary division of a compound 
leaf (Fig. 80). 
pinnate: of a compound leaf when the leaflets are 
arranged along a rachis (Fig. 80). 
pinnately trifoliolate: a compound leaf with three 
leaflets, with the terminal leaflet on an extension 
of the rachis (Fig. 80). 
pistil: the united carpels of a syncarpous gynoecium 
or a single carpel of an apocarpous gynoecium. 
pistillode: a sterile pistil, often rudimentary. 
placenta: tissue from which ovules arise. 
placentation: arrangement and position of the 
placentas in the ovary (Fig. 79). 
pleiochasium: a cyme with more than 2 lateral 
branches. 
plumose: feather-like. 
plurinerved: with several to many nerves. 
pod: a legume; a dry fruit dehiscing by two sutures 
and derived from a unicarpellate, unilocular 
ovary; found in Caesalpiniaceae, Fabaceae and 
Mimosaceae (Fig. 4). 
