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Ordinary epidermis
Guard cells
Thick cuticle
Thicker cuticle
Thin cuticle
Parasitic plant
Petal epidermis
Sclerified epidermis
Papillose epidermis
Sculptured cuticle
Elaborate cuticle
Cuticular horns
Radial walls
Cuticle proper
No epidermis
Epidermal peels
Cycad peel
Paradermal
Typical stoma
Sunken stoma
Stomatal orientation 1
Unusual orientation 2
Artifact
Stomata and fibers
Stomatal crypts
Crypts, mag.
Crypt margin
Non-crypt
Water lily
Stomatal channels
Groove, hi mag
Subsidiary cells
Ledges
Papillae
Trichome
Uniseriate hair
Peltate hair, mag
Peltate, lo mag
Branched hairs
Trichome base
Lithocyst, Ficus
Lithocysts, hemp
Bulliform cells
Grass epidermis
Multiple epi
Uniseriate?
Peperomia

Fig. 10.3-14. Transverse section of water lily leaf (Nymphaea). This micrograph shows the upper epidermis (the palisade parenchyma is just below it) and it contains many stomata. The lower epidermis is not visible, but it has no stomata. Can you explain the adaptive significance of this anatomy?

            This is a species of water lily whose leaves float on the surface of a pond or lake. If it were like an ordinary leaf, it would have the majority of its stomata in the lower epidermis, pressed against the water’s surface – they would be unable to absorb any carbon dioxide from the atmosphere. This arrangement – having all the stomata in the upper epidermis – permits the leaves to absorb carbon dioxide. It also causes them to lose much more water, but that is not much of a problem for water lilies. This unusual anatomy would not be adaptive for most terrestrial species, but it is functional in this particular habitat.