Article: The Lepidodendroid stoma

Detailed investigations have been made of the stomata of several lepidodendroid species using cuticle preparations from compressions together with sections and peels from petrified material. The scanning electron microscope has allowed more critical observation of the compression preparations than has been previously possible. Structures are shown within the guard cells which are tentatively interpreted as the remains of lignified wall thickenings. This is the first time such structures have been shown in these plants.