Abstract: Epidermal micromorphology of 20 species ferns leaves from different families and genera in Yunnan were observed by optical microscope. The results showed that: different appendages exist in different leaves surface, some species have no appendage. There are eight stomatal apparatus types: polocytic, axillocytic, aotinocytic, diaisocytic, anomotetracytic, copolocytic, coaxillocytic and anomocytic types. The stomatal apparatus have multi-type phenomena, all the stomata are hypostomatic types, while their distributive modes and sizes also varies. The leaf epidermal cell micromorphology from different genera and families show certain differences, basically have irregular type, multilateral type or regular strip type. The leaf epidermal cell anticlinal walls are mainly corrugated, deep wavy or wavy. The results in this study provide basic references for systematics and evolution of ferns.

Key words: fern, stomatal apparatus, epidermis, micromorphological feature