 The Leaves are Microphylls and
have a single Vascular Bundle that is connected
to the Stele in the stem by Leaf Traces.
The latter can be seen in the Cortex of the Stem.
Stomata are present.
The
Mesophyll (middle leaf) is undifferentiated
and has a uniform appearance.
Some
species are Isophyllous while others are Anisophyllous.
Leaves associated with Sporangia are
called Sporophylls. These can be similar
to vegetative leaves or they may be distinct. The
latter occurs when the sporophylls are assembled into a Cone
(Strobilus).
In some cases complex Gemmae are produced in place of leaves. They have preformed Shoot and Root Apical Meristems plus Vegetative
Leaves. They readily produce new plants when they land in a favorable environment.
Alpine plant with Gemmae - These could be handy in a
challenging environment where the next Lycopodium could be on the opposite side
of the valley.
Macrophoto of a Gemma
Microphoto of a Gemma
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Lycopodium phyllanthum Cones (above
& below): Ecah Sporophyll has one Sporangium.
The Sporophylls differ from the Vegetative Leaves.
The yellow areas along these stems (above & below) have Sporangia
at the base of each leaf. Otherwise the Sporophylls are identical to vegetative Leaves.
This a close-up which shows the bean-shaped Sporangia at the base of Isophyllous
Sporophylls.
Photo
by Angel Maden
(Color by DTW)
SEM photo of Lycopodium-type Sporangia Shamelessly colored by DTW.
The Vegetative leaves in this species are needle-like. The sporophylls of the cone are
greatly reduced in size and have a different shape. The leaves are thus
Anisophyllous.
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