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The leaves of Glossopteris are characterized by their distinctive tongue shape that gives them their name, as well as their reticulate venation. The leaves were either widely spaced on long stems, or were densely helically arranged on short shoots. Glossopteris bearing plants grew as woody, seed-bearing trees and shrubs.
The leaves are 8–10 centimetres (3.1–3.9 in) long, [5] petiolated, alternate, tough, leathery, and heart-shaped, with toothed and spiny margins. It is a monocot with reticulate venation. The midrib of the underside of the leaf is also provided with spines. The flowers, very fragrant, are small, yellowish or greenish, gathered in axillary ...
For instance, the parallel venation found in most monocots correlates with their elongated leaf shape and wide leaf base, while reticulate venation is seen in simple entire leaves, while digitate leaves typically have venation in which three or more primary veins diverge radially from a single point. [32] [25] [30] [33]
Being one of the more visible features, leaf shape is commonly used for plant identification. Similar terms are used for other plant parts, such as petals, tepals, and bracts. Oddly pinnate, pinnatifid leaves (Coriandrum sativum, coriander or cilantro) Partial chlorosis revealing palmate venation in simple leaves of Hibiscus mutabilis
Leaf venation is of the striate type, mainly arcuate-striate or longitudinally striate (parallel), less often palmate-striate or pinnate-striate with the leaf veins emerging at the leaf base and then running together at the apices. There is usually only one leaf per node because the leaf base encompasses more than half the circumference. [31]
When the leaves are dried along the secondary veins, the leaves become disfigured having a chartaceous characteristic that is a flat paper trait. The leaves are also narrower in shape. The venation in the leaves run in a reticulate venation where the midrib, which gives support to the leaf, and secondary (and even tertiary) veins are seen.
Its leaves are simple and petiolate, with alternate phyllotaxy. The leaf shape is ovate while the tip is acute, and the margin is serrated. Venation is unicostate reticulate, meaning the leaves' veins are branched or divergent. Their surfaces are glossy. [6] Free lateral stipules are present.