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Abnormal stomatal development in foliage leaves of Begonia aridicaulis
by Dehnel G. S. (1961)
George S. Dehnel
in American Journal of Botany 48: 129–133. –
The results of 2 types of aberrant stomatal development in abaxial epidermis of normal laminae of B. aridicaulis are discussed and illustrated.
The more common is a so-called persistent stomatal initial that is an essentially circular cell (in face view) with chloroplasts and a wall of uniform thickness.
The other type of anomalous development yields a single guard cell, which possesses chloroplasts, differential wall thickening, rarely a pore, and a form characteristic of a normally paired guard cell.
Both types of cells may either be isolated or occur variably in close relationship to normal stomata.