Leaf anatomy of the South African Danthonieae (Poaceae). XIV. Pentameris dregeana

Abstract

Transverse sections and abaxial epidermal scrapes of leaf blades of Pentameris dregeana Stapf, both of herbarium specimens and of freshly fixed material, were examined by light microscopy. The anatomical structure was found to be basically uniform in a representative sample. A few somewhat atypical specimens, how'ever, showed epidermal similarities with  Pentaschistis colorata (Steud.) Stapf. A comparison with other danthonoid grasses revealed some specimens identified as  Pentaschistis colorata var.  polytricha Stapf which resemble  Pentameris dregeana very closely in leaf anatomy. A definite gradation in leaf anatomy between  Pentameris dregeana and  Penta­schistis colorata appears to exist and. consequently, it is proposed that the affinities of Pentameris dregeana lie with this group of  Pentaschistis species rather than close to any of the other  Pentameris species.