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REJDALI, MOH, 1992. A numerical analysis of Sideritis L. (Lamiaceae) from North Africa. A numerical analysis is shown to be useful means of discriminating taxa at all levels of the hierarchy in the genus Sideritis. This analysis supports both the separation of the genus into the two sections recognized by Bentham, the three groups of Briquet's treatment and the four groupings as suggested by various lines of evidence presented by Rejdali (1988).

REJDALI M., 1991. Leaf micromorphology and taxonomy of North African species of Sideritis L. (Lamiaceae). This study reports on the structure of trichomes, epidermal cells, stomata and venation patterns. The trichomes are either glandular or eglandular. The latter are unicellular or multicellular, soft or rigid pointed hairs. The glandular hairs are short or long stalked, the latter are generally flattened and may be sessile. The epidermal cells are variously shaped with sinuous or straight walls usually randomly orientated. Stomata are either anomocytic or diacytic and evenly distributed throughout the epidermis without any definite pattern of orientation. Venation is of the semicraspedodermous type.

REJDALI, M., 1990. Seed morphology and taxonomy of the North African species of Sideritis L. (Lamiaceae). Seed morphology data are shown to support data from general morphology and palynology; they can be used for taxonomy at the sectional and specific levels. At times clear differences are apparent at the infraspecific level. Seed sculpturing was found to be of great value for separating taxa at all levels of the hierarchy.

The flavonoids, both external aglycones and vacuolar flavonoid glycosides, have been identified in the aerial parts of endemic North African Sideritis species. The flavonoids produced by these African species are very similar to those produced by Spanish species, being mainly 7-allosylglucosides of 8-hydroxyflavones. Two new flavonoid glycosides, apigenin and luteolin 7-allosylglucosides, have been identified in these plants. Species of the section Sideritis are characterized by the accumulation of the 7-glycosides of 8-hydroxyflavones (isoscutellarein, hypolaetin and their methyl ethers) whereas those of section Hesiodia accumulate 7-glycosides of the common flavones (apigenin, luteolin and chrysoeriol).

This paper deals with the description of two new species of Sideritis (Labiatae) endemic to Morocco. Both species are of relatively narrow geographical distribution. One species is described for the first time, while the other is raised from a variety, having been incorrectly placed by Maire as a variety of S. ochroleuca Noe.