Leaf or leaflet lamina transverse section

The shape of the leaf or leaflet (phyllodes are treated as leaves), in cross-section, at or around the lamina mid-point. Note that in dried material, this character may be obscured by the pressing/drying process, particularly amongst taxa with soft (herbaceous) leaves.

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Rolled or circluar

The leaf or leaflet is approximately circular in cross-section. The leaves may appear  solid , as are the spiny phyllodes of some Daviesia spp., (e.g. Daviesia genistifolia or the leaf or leaflet margins are strongly rolled upwards or downwards (i.e. involute or revolute) forming a tube.

Four-angled

The leaf or leaflet is square (four-angled) in cross-section as in some Mirbelia species.

Three-angled

The leaf or leaflet is triangular (three-angled) in cross-section as in some Dillwynia species.

Flat (horizontally compressed)

The leaf or leaflet lamina is compressed  top-to-bottom ; i.e. broadest on an axis perpendicular to the stem.

Flat (vertically compressed)

The leaf or leaflet lamina is compressed  side-to-side ; i.e. broadest on the same axis as the stem. This condition occurs amongst some Daviesia species, and is commonly associated with sub-parallel leaf venation.

V-shaped or longitudinally folded

The leaf or leaflet lamina is folded (either upwards or downwards) along the mid-rib. The leaf or leaflet may appear v-shaped in section, or in the extreme case, opposite margins are touching (e.g. Gastrolobium laytonii).

Broadly u-shaped

The leaf or leaflet lamina is curved (either upwards or downwards) either side of the midrib, appearing u-shaped in section. Note that this condition may be poorly preserved amongst pressed/dried specimens.

Spirally twisted

The leaf or leaflet is  cork-screwed , the midrib passing through one or more rotations (e.g. Daviesia spiralis).